ATI Crossfire [Archive] - Beyond3D Forum

Dave Baumann

25-Sep-2005, 12:53

<a href="http://www.beyond3d.com/reviews/ati/crossfire/"><img border="1" src="http://www.beyond3d.com/siteimages/b3dsmall.gif" align="right" width="100" height="66"></a>When ATI initially unveiled the Radeon X800/X850 Crossfire platform we raised questions as to its timing in relation to the availability of ATI's next generation of graphics. Since Computex, its become obvious that ATI's next generation R520 product has suffered some months worth of delays, however what they didn't predict is that so too would the Crossfire platform. Now we meet with the situation that the launches of X850 Crossfire and R520 are very close, almost limiting this Crossfire performance article to a proof of concept piece. However, this does give us the opportunity to test Crossfire and see where the strong and weak points of the implementation lie.

This article provides a refresher to the Crossfire technologies, updated with the most recent pertinent details, takes a look at the actual hardware as well as looking at performances of the X850 Crossfire configurations. <a href="http://www.beyond3d.com/reviews/ati/crossfire/">Click here to read more about Crossfire</a>.

PeterAce

26-Sep-2005, 14:26

Great artice Dave.

Some great performance benefits (when GPU limated).

I'm a little disapointed about the 1600x1200 60Hz limation (as a CRT user). But as the next-gen of cards come out so soon then it doesn't really matter.

BTW: On the 'Radeon XPRESS 200 Crossfire Edition' page you have the Table title 'ASUS A8N-SLI Deluxe Details'.

Joe DeFuria

26-Sep-2005, 14:28

Very good read...but with disappointing results for x-fire itself. Most disappointing is the situation with the super AA modes. They still haven't worked out the issues wrt using DVI vs. PCI-e bus?

Seems to be very good news on the compatibility / stability front, but it still just looks like x-fire is a generation pre-mature, IMO. If they can get super AA sorted reasonably soon, that'd be cool, but given how long it's taken so far, I wouldn't be holding my breath for it.

Looks to me like I'd have to wait for nVidia SLI / ATI X-Fire Version 2 before I'd give either one any serious consideration.

Geo

26-Sep-2005, 14:41

AT LAST! :razz:

Should one not get too hopeful in a forward-looking manner about this simple statement of fact, given that the hints are they might have worked the ROPs over pretty well for R5xx?

and in the case of the R300 and R420 series this goes up to 6 samples.

Lots of gains in the 90%+ area when not cpu-limited, which was nice to see.

14xAA screenie does cause a bit of salivating, I must admit. :smile: Pity about the performance hit tho, and I hope they follow thru on the promise to address it relatively quickly.

Did you play around with any other games without benching them, just to see how they looked? Any subjective comments, or visual anomalies noted?

Seems like a reasonable (if delayed) start for ATI. But much like SLI, what will really matter is how it all looks in another six months or so. . .

26-Sep-2005, 14:56

Great read (as all of the articles here). I was supprised it was able to do as good as it did in some cases. And yes pitty about the super AA modes as that is what I was really interested in. It will be nice to see if newer cat drivers fix that issue and how x-fire plays out in the R520 serries....

Joe DeFuria

26-Sep-2005, 15:05

What is it about the compositing for Super AA that makes it "so difficult" to do via DVI? SuperAA mode should be the only one that requires a blend...but why is this a problem? Does the compositing chip have the ability to do the blend, or must that be done on the master graphics chip? (Or is it currently being done on the graphics chip, and they are working on the software to get the compositing chip to do it?) I just don't understand what the inherent "issue" is with Super AA that makes it that much more difficult than the other modes.

Dave...can you shed any light on this?

Edit: I re-read the section on Super AA which answered most of the questions above:

1) Yes, the graphics chip on the master is currently doing the blend
2) ATI claims that the blend will be working with the composite engine in the "next few driver releases", which should then hopefully address the performance issue. (Though I guess the performance bottleneck will depend on how fast the composite engine can perform the blend, compared to the graphics chip.)

It still seems to me that this is a very simple blend operation...and I can't think of why it should be so difficult to "program" the composite engine assuming it can be done. This is why I'm a bit leery of how things will turn out...

martrox

26-Sep-2005, 15:31

Enjoyable and interesting read.......

tEd

26-Sep-2005, 15:42

Well now we know it.

While the results are promising , the 1600x1200@60 limitation plus the rather disapppointing SuperAA scores would make it very useless to me.

good article dave

Geo

26-Sep-2005, 15:56

Well now we know it.

While the results are promising , the 1600x1200@60 limitation plus the rather disapppointing SuperAA scores would make it very useless to me.

Nice summation for the moment, alas. Double-whammy. SuperAA would be the saving grace for many on the high-res front, and the performance isn't there yet.

But, again, given the SLI experience, coming to definite conclusions on release is very premature. It seems to me they are off to a better start than NV had, relatively, tho obviously still behind on a few key fronts in an absolute sense. The whole mobo thing might be more important, if they don't either get compatibility with NV mobos, or don't get the kind of penetration they'd like with their own --and certainly NV was/is in a much stronger position in the mobo market than ATI is today to help drive that aspect.

MuFu

26-Sep-2005, 16:01

Nice summation for the moment, alas. Double-whammy.

Yes! That's really rather unfortunate.

Performance and compatibility characteristics sound very encouraging.

bigz

26-Sep-2005, 16:03

good read Dave, thanks!

MuFu

26-Sep-2005, 16:13

Even if they sort SuperAA out, IMHO nV have a more attractive set of AA options at the moment. Will that change with R(V)5xx? We'll see. As it stands, Crossfire is too little, too late.

BTW, excellent article blah blah etc etc... don't think there's actually been a bad one to date!

Slappi

26-Sep-2005, 16:18

Nice article.

Still waiting for a MB+GC purchase. Guess I need to wait until the 5th of October to see if that Res limitation is still there on the new cards.

Himself

26-Sep-2005, 16:25

Considering I only have a 9800 pro, and I'm wondering what game will make me want to upgrade, all this seems rather extreme, lol.

You need to buy a new motherboard, one that will work with crossfire, not one with all the features you want (Gb nic), and two expensive video cards for the sake of what? Geometry same speed as a single card, cpu limited games will see no benefit, basically faster AA/aniso really, and the extra AA is foobar to me right now. Not that I found SLI compelling either, mind you.

Sounds like it's only about bragging rights for geeks. :)

digitalwanderer

26-Sep-2005, 16:33

Sounds like it's only about bragging rights for geeks. :)
Considering all it's drawbacks and lack of cost effectiveness I'd consider it more bragging rights for stupid geeks. ;)

trinibwoy

26-Sep-2005, 16:35

Even if they sort SuperAA out, IMHO nV have a more attractive set of AA options at the moment. Will that change with R(V)5xx? We'll see. As it stands, Crossfire is too little, too late.

I think TechReport found SuperAA to be of higher quality than Nvidia's SLI AA.

bigz

26-Sep-2005, 16:45

I think TechReport found SuperAA to be of higher quality than Nvidia's SLI AA.
Scott had a lot of issues with SLIAA AFAIK

MuFu

26-Sep-2005, 16:46

It's just a personal preference - one that's changed since nV introduced TR modes. I tend to agree with [H]'s conclusion on the matter (although haven't seen a 7800 in action so should probably STFU at this point).

http://www.hardocp.com/article.html?art=ODE1LDQ=

Randell

26-Sep-2005, 17:19

Considering I only have a 9800 pro, and I'm wondering what game will make me want to upgrade, all this seems rather extreme, lol.

FEAR? the demo makes my 6800GT weep. Though I cannot see a sensible reason for XFire/SLI.

digitalwanderer

26-Sep-2005, 17:30

<sigh>

Having just wrote it in the benchmark thread, I thought I'd make me feelings known here to:

Crossfire = DOA

End-o-story. :(

Hubert

26-Sep-2005, 17:50

My issue (owner of a X800XL) is lack of extended instruction capabilities for the R4xx family ( SM 3.0 ), which really pushes me to rather upgrade than "extend" the performance of my current card. Even if I could use it with my NF4 motherboard.

As for the max resolution issue, it really hurts where it counts. Because LCD's do not have that high of a resolution, so the only area where the high resolution capabilities would shine is on CRTs, and there you have the 60 Hz limitation. ( I understand that's inherent to DVI, still ...)

The Super AA performance is the least I am concerned of. They'll probably sort it out soon.

It feels like Ati accepted to dance just for they can't be blamed not doing it ...

Just give me my X1800 XL, and you don't see me for another 2 years ...

digitalwanderer

26-Sep-2005, 17:52

My issue (owner of a X800XL) is lack of extended instruction capabilities for the R4xx family ( SM 3.0 ), which really pushes me to rather upgrade than "extend" the performance of my current card. Even if I could use it with my NF4 motherboard.
I still don't see the real need for SM3.0 support yet, is it really a big influencing factor already?

I was hoping to push off worrying about getting a card with SM3.0 support until after Xmas, you think I'm being too optimistic?

CMAN

26-Sep-2005, 18:05

I still don't see the real need for SM3.0 support yet, is it really a big influencing factor already?

I was hoping to push off worrying about getting a card with SM3.0 support until after Xmas, you think I'm being too optimistic?

Why wait till after Xmas? A 3.0 card would be a nice self present.

I think everyone is being too harsh on Xfire. I say wait until next week. I agree currently there are little to no reason to use Xfire with the X8xx series, but next week will be different. If ATI fixes the SuperAA, and the X1K series have dual DVI output, then the two major deficencies will be fixed. Just my opinion.

epicstruggle

26-Sep-2005, 18:23

I think everyone is being too harsh on Xfire. I say wait until next week. I agree currently there are little to no reason to use Xfire with the X8xx series, but next week will be different. If ATI fixes the SuperAA, and the X1K series have dual DVI output, then the two major deficencies will be fixed. Just my opinion.
Yep, i think the new cards coming out in the next week or two will redeem xfire.

epic

Himself

26-Sep-2005, 18:31

FEAR? the demo makes my 6800GT weep. Though I cannot see a sensible reason for XFire/SLI.

Downloaded the demo twice, first time I was like blah... forgot about it, read some hype about it again.. downloaded it again, went blah again.. :)

digitalwanderer

26-Sep-2005, 18:33

Why wait till after Xmas? A 3.0 card would be a nice self present.
Yeah, but I'm a cheap bastard and if I wait a few months after Xmas I'll get a lot more bang-for-buck. ;)

I think everyone is being too harsh on Xfire. I say wait until next week. I agree currently there are little to no reason to use Xfire with the X8xx series, but next week will be different. If ATI fixes the SuperAA, and the X1K series have dual DVI output, then the two major deficencies will be fixed. Just my opinion.
I'm not giving any companies the benefit of the doubt anymore until they can prove it, but I will wait and see...it's not like there's a lot else I could do anyways. ;)

Pete

26-Sep-2005, 18:37

Great article, Dave. I'm disappointed in XFire's shortcomings, too. I think ATI should have held off on Xfire until the RX1 generation. But maybe they were looking to "reward" X800 purchasers with a test run of the product, in anticipation of a fuller realization with R520+.

Edit: This test run may also be to recoup some R&D spending before the "real" deal with R520, but I can't imagine it getting much of a production run, even on the coatails of SLI's PR. And you have to think they're going to get more than a few emails about high-res CRT support.

I just can't figure out why ATI couldn't sacrifice and add enough RAM to the CE to remove the refresh rate limitation, if only in the name of good PR.

digiEdit: Could be, dw, but I can't imagine they'll sell a lot of these.

Again, ATI, wouldn't it have cost less in the long run to slap some RAM onto the CE than to suffer the bad press and inevitable support calls? Maybe there wasn't space on the current board, but still.

I guess next-gen games, like those based on the UE3 engine, may make X800 XF look better in that 12x9 will be a more realistic res for very playable framerates. But, until then, you've got a lot of PO'ed CRT owners.

digitalwanderer

26-Sep-2005, 18:47

But maybe they were looking to "reward" X800 purchasers with a test run of the product, in anticipation of a fuller realization with R520+.
Or mebbe looking to offload a lot of R4xx chips in the channels before the R520 is released....but don't listen to me as I'm a bit cynical today. http://www.rage3d.com/board/images/smilies/bleh2.gif

Kanyamagufa

26-Sep-2005, 18:48

I think the most impressive thing about these Crossfire benches are its performance compared to the 6800 Ultra running in SLI. Obviously everyone's looking at the GTX in these reviews, but thats nVidias next generation part, and so I will wait until next week for my final opinion.

But when you compare two of the same generation parts to each other (the X850 and the 6800 Ultra) in their respective dual GPU setups, Crossfire kicks some serious ass. I think ATI did good, even if it is too little too late.

Just my two cents.

Moloch

26-Sep-2005, 18:52

Nice review.
Pity about the limitations from the single link dvi as well as superaa.
Too little to late imo.

26-Sep-2005, 18:52

But when you compare two of the same generation parts to each other (the X850 and the 6800 Ultra) in their respective dual GPU setups, Crossfire kicks some serious ass. I think ATI did good, even if it is too little too late.

Yea I think thats where the merits of xfire lies. I and don't agree with the DOA of digi as it seems to me xfire was usally faster than the 6800U-SLI. Granted xfire has some serrious shortcomings that are the real issue...imho...

Joe DeFuria

26-Sep-2005, 18:56

Yes, performance and compatibility wise, x-fire looks pretty good so far. The problem from where I see it for ATI is that x-fire on R4xx is pretty much senseless. For those already with an R4xx ATI card running on a PCI-E mobo:

1) You have to buy both a x-fire mobo and and x-fire master card
2) You end up with a very fast SM 2.0 implementation
3) You could probably spend the same amount of money and keep your existing PCI-E mobo, get a higer end SM 3.0 card (R520 based or latest nVidia). It would be competitive in speed, and more fully featured.

On top of that, if you have a CRT you get hit with the resolution limitation...and the feature that could help negate that (SuperAA) is still missining in action due to major performance degredation.

I still really can't beleive that X-Fire was launched without SuperAA "working" after all this time.

On R5xx, X-Fire should be as just as viable an option (read: the hardest of the hard-core niche market) if not more so than nVidia's solution...but they need to get SuperAA sorted.

digitalwanderer

26-Sep-2005, 19:02

I still really can't beleive that X-Fire was launched without SuperAA "working" after all this time.
Yup, or with the 16x12 @ 60Hz limitation. Both of those are show-stopper bugs for the demographic they're aiming to sell these to. :(

trinibwoy

26-Sep-2005, 19:07

Yea I think thats where the merits of xfire lies. I and don't agree with the DOA of digi as it seems to me xfire was usally faster than the 6800U-SLI. Granted xfire has some serrious shortcomings that are the real issue...imho...

That may be true but it still doesn't matter since the 6800U is essentially EOL. (And the X850XT was already faster than the 6800U in single card matchups anyway).

The true value of Crossfire will be apparent come next week I think.

Joe DeFuria

26-Sep-2005, 19:13

Yup, or with the 16x12 @ 60Hz limitation. Both of those are show-stopper bugs for the demographic they're aiming to sell these to. :(

(Yes, I read your posts as long as they are not on the political forum).

No, I can completely understand the 16x12 limitation on the R4xx implementation. Basically, ATI had to make a choice wrt R4xx:

Either

1) Let existing users keep their current R4xx card and have the resolution limitation,

or

2) make new R4xx XFire customers buy two new cards.

For the R4xx generation, I think ATI made a legitimate choice.

26-Sep-2005, 19:21

That may be true but it still doesn't matter since the 6800U is essentially EOL. (And the X850XT was already faster than the 6800U in single card matchups anyway).

I dont agree with that at all (about the not matter). Why? I was expecting xfire not to be as good as it was. I mean there are a lot of things to deal with on mulit-graphic board to ensure data is being shared and sent in an efficent mannor. So I expected xfire to be slower that what it was for its first pass. Thus I expected it to be slighly slower than the 6800U until ATI tweaked their drivers and learned more about how to write efficent drivers for xfire (and yes I know its been delayed so long which has given ATI more time to play with drivers)...

digitalwanderer

26-Sep-2005, 19:33

No, I can completely understand the 16x12 limitation on the R4xx implementation. Basically, ATI had to make a choice wrt R4xx:

Either

1) Let existing users keep their current R4xx card and have the resolution limitation,

or

2) make new R4xx XFire customers buy two new cards.

For the R4xx generation, I think ATI made a legitimate choice.
I agree they made a legitimate choice given their options, but that still doesn't mean I like Xfire's limitations. :(

Dave Baumann

26-Sep-2005, 19:50

There was a third choice: Use any card they please but do it over the PCIe bus. Trade off there was sucky performance.

bigz

26-Sep-2005, 19:54

I agree, ATI did the right thing in not turning against many many thousands of customers who have Radeon X8x0 series video cards. Having said that, I can't help but feel that this is proof in the pudding that they were caught with their pants down in July last year. :(

trinibwoy

26-Sep-2005, 19:56

I dont agree with that at all (about the not matter). Why? I was expecting xfire not to be as good as it was. I mean there are a lot of things to deal with on mulit-graphic board to ensure data is being shared and sent in an efficent mannor. So I expected xfire to be slower that what it was for its first pass. Thus I expected it to be slighly slower than the 6800U until ATI tweaked their drivers and learned more about how to write efficent drivers for xfire (and yes I know its been delayed so long which has given ATI more time to play with drivers)...

Are you saying that you find the current state of Crossfire to be impressive given the length of time ATi has been working on it? I would agree with this - they were literally forced into going dual-GPU and considering they've had to work with hardware that wasn't designed with Crossfire in mind then yes it is quite a technical achievement. But in terms of value to the consumer and market penetration, X850 Crossfire seems to be way too late to be of any significance. R520 Crossfire should be very interesting.

Joe DeFuria

26-Sep-2005, 19:57

There was a third choice: Use any card they please but do it over the PCIe bus. Trade off there was sucky performance.

Yeah, and if memory serves, that was where they were initially leaning based on the early rumors. Given the spot that ATI was in (behind the SLI marketing 8 ball), I'd say they ultimately made the right choice.

ATI not considering multi-board solutions from the get-go with r300/r400 products is what put them in the reactionary position. X-Fire on R5xx should at least be a good competitor for nVidia SLI...each implementation with pros and cons.

26-Sep-2005, 19:59

Are you saying that you find the current state of Crossfire to be impressive given the length of time ATi has been working on it? I would agree with this - they were literally forced into going dual-GPU and considering they've had to work with hardware that wasn't designed with Crossfire in mind then yes it is quite a technical achievement. But in terms of value to the consumer and market penetration, X850 Crossfire seems to be way too late to be of any significance. R520 Crossfire should be very interesting.

yea thats what I was kind of going at, as given that xfire was a "knee jerk reaction" (hehe) then it was impressive that its gains were as good as it was given the fact the hardware was not designed for it. And yes the drivers seem to be good...I mean opengl on ATI still sucks so at least they have xfire right :) :) :) (joking)

digitalwanderer

26-Sep-2005, 20:02

There was a third choice: Use any card they please but do it over the PCIe bus. Trade off there was sucky performance.
How "sucky" are we talking about?

Joe DeFuria

26-Sep-2005, 20:07

How "sucky" are we talking about?

http://www.beyond3d.com/reviews/ati/crossfire/index.php?p=17

Well, it looks like at 1600x1200, you'd never get more than 30-40 FPS...in other words, using PCI-E only, you could actually end up SIGNIFICANTLY SLOWER than a single card...

Edit: Well...it's not quite that bad since with the other x-fire modes you are only sending about 1/2 the data...so you would be capped to about 60-80 FPS at 1600x1200.

digitalwanderer

26-Sep-2005, 20:12

http://www.beyond3d.com/reviews/ati/crossfire/index.php?p=17

Well, it looks like at 1600x1200, you'd never get more than 30-40 FPS...in other words, using PCI-E only, you could actually end up SIGNIFICANTLY SLOWER than a single card...

Edit: Well...it's not quite that bad since with the other x-fire modes you are only sending about 1/2 the data...so you would be capped to about 60-80 FPS at 1600x1200.
Ah, thanks.

That explains why they chose to do what they did at least, but I still think the current limitations are too much of show-stoppers. :(

Dave Baumann

26-Sep-2005, 20:17

I just can't figure out why ATI couldn't sacrifice and add enough RAM to the CE to remove the refresh rate limitation, if only in the name of good PR.Again, ATI, wouldn't it have cost less in the long run to slap some RAM onto the CE than to suffer the bad press and inevitable support calls? Maybe there wasn't space on the current board, but still.
You've got a cost issue for starters. Also, I doubt the FPGA device has a memory interface as it has its own limited buffering/memory.

It still seems to me that this is a very simple blend operation...and I can't think of why it should be so difficult to "program" the composite engine assuming it can be done.
The only thing that springs to mind could possibly be Gamma corrected AA? Bear in mind that what reaches the composite engine is already at the display resolution, so any AA will have already have been downsampled at that point and hence gamma correction already appled to each of the two images that need to be blended together by the FPGA. I that were the case, though, I'm not sure how doing it on the graphics chip, as they are now, would be any different, unless they are not downsampling on the current system.

Edit: Well...it's not quite that bad since with the other x-fire modes you are only sending about 1/2 the data...so you would be capped to about 60-80 FPS at 1600x1200.
No, in the split modes you are still sending a full frame, just part os the image are "black". I do now wonder how much data they are sending down with Super AA though...

Joe DeFuria

26-Sep-2005, 20:24

I that were the case, though, I'm not sure how doing it on the graphics chip, as they are now, would be any different, unless they are not downsampling on the current system.

Yeah, I just can't figure out what the "problem" could be.

No, in the split modes you are still sending a full frame, just part os the image are "black". I do now wonder how much data they are sending down with Super AA though...

Hmmph. That seems really inefficient, but I can see why that would be the case when using the compositor chip... which as far as I can tell combines with minimal logic and is pretty "dumb." However, if stuff was sent across the PCI-E bus and combining done with the graphics chip (which has access to memory, etc), I would think that they would not have to send "black", but could just send the actual rendered pixels across the bus.

Himself

26-Sep-2005, 21:11

I wonder if it would have been possible to do the xfire thing with a third card instead of having this S&M thing on the go? Have the two dvi outputs go to a third card with the compositing bits on it, with ram even for a framebuffer. And the only reason for it being a card in a slot would be for control reasons, and even that you could embed into the dvi streams.

Not sure why they have to disable pipes and the like, if one card is waiting for the other, so what? If it's waiting instead of being disabled, you are still saving some power.

digitalwanderer

26-Sep-2005, 21:27

Razor1

27-Sep-2005, 06:58

they should have just waited a week for the r520 that would probably help out crossfire sales :/

Hubert

27-Sep-2005, 09:36

I still don't see the real need for SM3.0 support yet, is it really a big influencing factor already?

I was hoping to push off worrying about getting a card with SM3.0 support until after Xmas, you think I'm being too optimistic?

Maybe not now, but I'd like to think my next card will handle at least 2006 titles, with decent IQ settings. (1280x1024 LCD) But who knows ? Maybe I'm just the victim of Nvidia's marketing. :D

Still, I have the impression that there are more and more applications advertised as SM 3.0. I mostly play RTS/RPG games, and it is questionable if SM 3.0 really makes a difference there, but still, I'd like to have my back covered.

Hubert

27-Sep-2005, 09:40

Edit: being just out of my league

dizietsma

27-Sep-2005, 11:51

I have no understanding at all why ATi allowed crossfire reviews now, could they not wait until after the r520 launch and then have a double whammy ?

What is the logic behind releasing it now ?

digitalwanderer

27-Sep-2005, 13:56

Edit: being just out of my league
:lol:

I feel that way all the time too! ;)

martrox

27-Sep-2005, 14:21

Just WTF is going on up there in Canada....eh?

digitalwanderer

27-Sep-2005, 14:48

Just WTF is going on up there in Canada....eh?
Hockey season must have started. http://mastabeta.com/forum/images/smilies/yep.gif

ondaedg

27-Sep-2005, 15:32

I guess I am one of the minority who is impressed with their solution. Guess I am going to have to get a new CRT so I can be disappointed with the resolution limitation.

martrox

27-Sep-2005, 15:53

Well....at least the crossfire chipset looks nice......
http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2542

Sxotty

27-Sep-2005, 17:02

I think the theory they have is that they get this out of the way. Sure it is underwhelming, but when the next gen parts launch everyone will forget this was underwhelming and they will be ecstatic about the xfire r520s.

WaltC

28-Sep-2005, 00:41

I have no understanding at all why ATi allowed crossfire reviews now, could they not wait until after the r520 launch and then have a double whammy ?

What is the logic behind releasing it now ?

Probably, information overload. I mean, why muck up the R5x0 release with lots of ancillary info about R4x0 X-Fire? Internet tech press being what it is, I think a simultaneous release of both at the same time would have been confusing (at least to some.) This way, the cat's out of the bag for R4x0 & X-Fire, and now ATi is free to expound voluminously on R5x0 in its incarnations, including R5x0 X-Fire.

I think it may even be the case that this "release" of R4x0 X-Fire specs was simply done to eradicate all doubts that ATi is very much in the X-Fire game, and that the best is yet to come.

For 3d, what is the advantage of buying a dual-slot PCIe mboard in the first place (over single-slot PCIe or AGP)? It's nV's SLI or ATi's X-Fire, only--seems to me. ATi seems to want it known that they are in the game for both R4x0 and R5x0 in a serious way--the timing here just simplifies the upcoming R5x0 release as ATi won't have to rehash all of the R4x0-specific stuff. My guess, anyway...

ondaedg

28-Sep-2005, 01:20

Pete

28-Sep-2005, 01:29

You've got a cost issue for starters. Also, I doubt the FPGA device has a memory interface as it has its own limited buffering/memory.Cost, certainly, but I wonder if it would have been worth sucking up to circumvent a IMO key limitation, at least with the great majority of current gen games that are playable above 1280x1024. The lack of a memory interface sounds pretty key, though, as that would probably entail even greater costs. I guess I could give ATI the benefit of the doubt.

Ailuros

28-Sep-2005, 01:57

I think the real question is why would they release it at the same time as R520? R4xx Crossfire is not going to be its ultimate high-end solution so wouldn't they release it before R520.

I think it's also safe to say that they had a timeline and as so many tech companies often do, they missed it. Nothing more, nothing less, IMO anyways.

The answer is in the last paragraph above. R4xx/CF sales would had been a lot higher if it would had been available months earlier. Only a few days before the official R520 launch, I'm not that sure that a R4xx owner would not rather buy a single R520 instead of a 2nd R4xx.

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Nice review as always :)

As for CrossFire overall I still don't see any real advantage over SLi. Users with a dual peg motherboard and already one R4xx or NV4x/Gx7 installed are obviously going to get a secondary GPU of whatever they have already, if a multi-GPU system appeals to them.

CarstenB

28-Sep-2005, 08:27

Is Crossfire not working as advertised except for the SuperAA problems, which the Catalyst team is reported to be working on? Meaning it is more of a driver problem than a hardware limitation?

From what I read in Dave Baumann's article, the Crossfire solution works very well in all the games tested. Sometimes I wonder why people expect more from ATI than is technically possible given the constraints of the earlier X800 series graphics adapters that were never designed with Crossfire in mind. Note, it is the boards that are not designed for multi-GPU operation. The chips themselves work very well in multi-GPU solutions as has been shown in other contexts.

Crossfire is probably too late to market with regard to the X800 adapters, but as a proof of concept it seems to work very well. We have yet to see what Crossfire can do with the new generation of adapters that are more likely to be designed with better support for Crossfire.

I can't see Crossfire as dead technology. This is just the beginning and the continuing competition with nVidia can only make all the multi-GPU solutions even better.

Ailuros

28-Sep-2005, 08:50

I can't see Crossfire as dead technology. This is just the beginning and the continuing competition with nVidia can only make all the multi-GPU solutions even better.

That's beyond doubt a reality, especially considering the promised improvements in the 8x.xx ForceWare series of drivers.

Sometimes I wonder why people expect more from ATI than is technically possible given the constraints of the earlier X800 series graphics adapters that were never designed with Crossfire in mind.

Were/are there actually the consumer expectations that are at fault here or the way CF has been marketed so far by ATI? What I'm failing to see so far are the supposed advantages claimed by ATI itself in the recent past.

OICAspork

28-Sep-2005, 10:04

Well....at least the crossfire chipset looks nice......
http://www.anandtech.com/cpuchipsets/showdoc.aspx?i=2542
It looks like Anand got a different reference board. They mention,

You may have noticed that the Gigabyte that we previewed several months ago controlled Crossfire with a "paddle board" similar to what we are accustomed to on NVIDIA. The AMD Reference Board does not use a paddle-card and all switching is done in the BIOS. In fact, the AMD Reference Board is capable of full auto-switching of single or dual video cards with no adjustments required in the BIOS if left in "Auto" mode. A number of video switching options are available to motherboard manufacturers.
Where as it appears Beyond3d got a paddleboard version.
In the case of this reference board in order to split the PCI Express lanes with 8 lanes going to each of the x16 connectors (and, in fact, to be able to physically insert the board) the transposer card needs to be removed from the second x16 PCI Express slot.
Dave, is the Beyond3d board older or just intended to give mobo makers more reference options? Did you try any overclocking with your testboard and if so were your results in line with anandtechs?

Dave Baumann

28-Sep-2005, 10:11

Mariner

28-Sep-2005, 10:50

- when I get five minutes to sit down and have a play with things I'll run some tests to see if it is actually needed or not, but right now things are a bit chaotic.

Fingers-crossed that this is because something interesting has arrived in the post! :smile:

OICAspork

28-Sep-2005, 11:57

As I wrote in the other thread, I'm not convinced that the "transposer" card is actually needed at all. There is a BIOS option, but the kits also came with these transposers - when I get five minutes to sit down and have a play with thingsI'll run some tests to see if it is actually needed or not, but right now things are a bit chaotic.
=D Woo, no hurries on the mobo info, given the likely reason for the chaos, I'm pretty sure no one here will mind the wait on more chipset info.

Geo

28-Sep-2005, 12:11

Well, you know how it is in the last days when you're getting ready for a trip to a party palace. :wink: Gotta find the sunblock, the dancing shoes, the silk shirts, etc.

http://paycay.forumactif.com/sutra18177.htm

28-Sep-2005, 14:19

=D Woo, no hurries on the mobo info, given the likely reason for the chaos, I'm pretty sure no one here will mind the wait on more chipset info.

DAMIT I WANT TO KNOW NOW!!!!! hehehehe Jk....thanks angain for the nuggets of info!

Mindriot

28-Sep-2005, 19:00

I really think Dave should just follow every post with "muahahahahahahah!"

BenSkywalker

28-Sep-2005, 20:13

Fundamentally there is little point in supporting high than single link DVI rates on this generation of compositing engine when the image from the slave board can only be at single link rates.

In realistic terms given the market they are going after this seems to be a much larger issue then the performance hit they would have taken going over the PCI-E bus. Performance numbers that were less then optimal would have been taken much better then not being able to handle high end displays native settings at all.

For the market CFire is going after nearly every user is pushing either a large widescreen Dell LCD or running a 21"/22" CRT(people who will spend well over $600 for a single gen of video cards). Given this extreme limitation I don't see why it is worth it for ATi to ship the product at all. They have their round of press, they have shown the proof of concept works, now move on to the R5x0 based CFire and let's see what it can really do.

29-Sep-2005, 14:17

For the market CFire is going after nearly every user is pushing either a large widescreen Dell LCD or running a 21"/22" CRT(people who will spend well over $600 for a single gen of video cards). Given this extreme limitation I don't see why it is worth it for ATi to ship the product at all. They have their round of press, they have shown the proof of concept works, now move on to the R5x0 based CFire and let's see what it can really do.

Probably right. But there are some out there like me that have a fast LCD at 1280x1024. That have an x8xx card now. In theory I could updrade to xfire for less than $400. Not saying it would be a wise, smart or good thing to do...just if I have this setup then I am sure others due as well...

BenSkywalker

30-Sep-2005, 06:47

Probably right. But there are some out there like me that have a fast LCD at 1280x1024. That have an x8xx card now. In theory I could updrade to xfire for less than $400. Not saying it would be a wise, smart or good thing to do...just if I have this setup then I am sure others due as well...

You won't though, that's the point. The people who purchase dual vid card setups are not those that buy tiny LCDs(overwhelmingly). Just looking at a master card, new mobo and power supply you are talking about dropping an extra ~$600(maybe ~$500... haven't seen the pricing for mobos yet) for a miniscule performance increase where as a singular GTX would bring you to a level where you are CPU bound in almost every situation(as will a single R520 I'm sure). There are a lot of people out there with 17"/19" LCDs- they aren't the ones buying 'SLI' setups for certain. If you go to most gaming forums even those with 2001/2005s are being told their displays are too limited in resolution to make dual card setups very useful for them(1600x1200/1680x1050).

30-Sep-2005, 13:48

I agree Ben on what you said...I was only trying to offer a counter point (and seems like a weak one at that)

Moloch

30-Sep-2005, 18:44

http://www.theinquirer.net/?article=26586
:shock:
Good goin' ati :roll:

Maintank

01-Oct-2005, 11:57

http://www.theinquirer.net/?article=26586
:shock:
Good goin' ati :roll:

*Shakes head*

Some people just never learn.

Shtal

03-Oct-2005, 06:04

The whole-point for me going for Cross-Fire NOT because I want best of the best frame rate that my eyes Wouldn’t not catch-it, but to enable 14X-AA {Multi-sample+Super-sample} (Best of the best eye-candy quality that you could get + HDR) at 1600X1200 @75 or 85 rerfresh rate. And play at Reasonable frame rate 60FPS+ any game.

But I would have to wait for ATI R580 or R600 in order I will upgrade my system.

weeds

04-Oct-2005, 06:30

Reward if Found: ATi Crossfire

http://voodoopc.blogspot.com/2005/10/reward-if-found-ati-crossfire.html

ATI's CrossFire: MIA

http://www.pcper.com/article.php?aid=171

ATI CrossFire MIA:

http://www.hardocp.com/index.html

BRiT

04-Oct-2005, 06:49

Crossfire found at NewEgg: (http://www.beyond3d.com/forum/showpost.php?p=584896&postcount=20)

hey, if anyone cares, though i doubt it:

http://www.techreport.com/
Radeon X850 XTs CrossFire Edition cards have been shipped to Newegg and we expect them to be posted any time now and we are confident no later than the end of the week. The X800 XLs and X800s will follow shortly after—around October 10th.
DFI's CrossFire Edition motherboards will also be available on Newegg at the end of this week/beginning of next. The others: MSI, ASUS, GBT, ECS, PCPartner, ABIT will follow will follow shortly thereafter.