usefulness of PCI Express in the near future?

[MistaPi]

When do you think the possibilities of PCIe will begin to be used? And are todays gfx cards to slow to see any benefits? Nevermind multi-board solutions and low-end TC, HZ.

In my opinion, PCI-E will have a major impact on how games are designed because you should be able to finally read from the graphic chip memory without breaking the streaming of the transactions between the core logic and the GPU. PCI-E is a point to point bus meaning that it works just like HyperTransport (dedicated upstream/downstream). On AGP, when you switch between read and write, you have to turn around and that takes time.

This should allow a new range of algorithms to be possible (like on consoles). You could use the GPU to calculate very quickly zone of dangers when the player is throwing a grenade (physic blast shadowing). The information could then by passed to your AI and Physics engine to help the AI makes a good decision on how to react to this event and to find out which objects should be impacted (where and how) by the blast. This kind of shadowing algorithm may or may not be efficient (compared to distributed ray casting) but it gives some ideas.

So overall, PCI-E won't have direct impact on rendering but it will have a big impact on engine design (only programmers will notice but games are going to get better more quickly).

All of this can be done on the CPU but people are going to start looking at the GPU to do other things than just graphics. All of this because of PCI-E.
_________________
Dany Lepage
Technical Director/Lead Programmer
Splinter Cell - X/3 (Chaos Theory)
Ubisoft Montreal

 

[fellix]

I've read somewhere, that full-duplex link can be usefull for procedural geometry processing where GPU have to continuously read vertex data from the L2 cache of the CPU, e. g. some sort of load distribution.

 

[digitalwanderer]

I've read somewhere, that full-duplex link can be usefull for procedural geometry processing where GPU have to continuously read vertex data from the L2 cache of the CPU, e. g. some sort of load distribution.

Really?

Soooo....y'think I should give up my quest for an AGP X1800/7800 and just get a PCIe mobo?

 

[Moloch]

Really?

Soooo....y'think I should give up my quest for an AGP X1800/7800 and just get a PCIe mobo?

well doing so open ups lots of doors.
You can use your venice now and an A64 X2 later

 

[digitalwanderer]

well doing so open ups lots of doors.
You can use your venice now and an A64 X2 later

I can do that now though with the mobo I got, it supports dual-core.

Not enough to make me upgrade, but thanks.

 

[Moloch]

I can do that now though with the mobo I got, it supports dual-core.

Not enough to make me upgrade, but thanks.

Ya but you can't get a X1900 now can you?
When did you get mobo

 

[fellix]

Anyway, I don't think that any present CPU is capable of handling geometry shading fast enough, no matter the bus interconnect, not counting all the phy & A.I. trash out there.
Just throw more cores or leave it to any future DX10 GPU w/ GS (or whatever it will be called).

 

[Npl]

I think it should help lots for PSX and maybe N64 Emulators which actually break down hard if framebuffer effects are emulated and used by the game (CPU operating directly on Framebuffer). Sadly I`ve never seen a comparison between AGP/PCIe on those, but a plethora of old Games which naturally show no difference...

Would give an crude Idea what to expect if Games are using both ways of the Bus

 

[Richteralan]

I can do that now though with the mobo I got, it supports dual-core.

Not enough to make me upgrade, but thanks.

If you wanna keep your AGP then you can get an Asrock 939Dual-SATA2.
It has both PEG and AGP

 

[digitalwanderer]

Ya but you can't get a X1900 now can you?
When did you get mobo

I didn't yet, but I'll be mailing out a check Monday for a Chaintech VNF4 Ultra a buddy offered me at a really good price.

 

[Moloch]

I didn't yet, but I'll be mailing out a check Monday for a Chaintech VNF4 Ultra a buddy offered me at a really good price.

I meant bubbles

 

[digitalwanderer]

I meant bubbles

Ah, sorry. My NF7-S died a few months back and I had to pick up a new mobo in a hurry, ended up upgrading a bit in the process.

My daughter's rig lost it's mobo too shortly after, and Snipe sent me a socket A mobo that I used with my old CPU/mem from Bubbles and she got a nice upgrade out of it.

My wife doesn't know it, but she currently has the slowest PC in the house.

 

[Moloch]

Ah, sorry. My NF7-S died a few months back and I had to pick up a new mobo in a hurry, ended up upgrading a bit in the process.

My daughter's rig lost it's mobo too shortly after, and Snipe sent me a socket A mobo that I used with my old CPU/mem from Bubbles and she got a nice upgrade out of it.

My wife doesn't know it, but she currently has the slowest PC in the house.

What was the cod for the mobo?

How fast is your wife's rig?

 

[digitalwanderer]

What was the cod for the mobo?

No clue. It went from sporadically unstable to wouldn't boot anymore. The 2400+ & 1Gb PC3200 went into my daughter's rig along with my old PSU and all work spiffy.

How fast is your wife's rig?

Promise not to laugh? It's a Tuly 1.4 @ 1.68 w/9600 pro...she hasn't been gaming much lately.

 

[Moloch]

No clue. It went from sporadically unstable to wouldn't boot anymore. The 2400+ & 1Gb PC3200 went into my daughter's rig along with my old PSU and all work spiffy.


Promise not to laugh? It's a Tuly 1.4 @ 1.68 w/9600 pro...she hasn't been gaming much lately.

Oh
a 1.68ghz tuly isn't bad for desktop work, my mom uses a 933 PIII with 640 ram (donated from my old computer).
Firefox crawls on it though, some sites will cause FF to peg cpu usage for a few minutes
I'm having trouble with my new rig as you've read, I think I might give up and give it to the place I bought the mobo/cpu/videocard from and have them throw some things at it and see how it responds- i.e different cpu, videocard and mobo.

 

[MistaPi]

What about DX10 virtual memory, wouldent PCIe be beneficial here?

Oh.. and not to sound bitter, but thanks for keeping it on topic you guys..

 

[JHoxley]

What about DX10 virtual memory, wouldent PCIe be beneficial here?

Yeah - the GPU is a shared resource under Vista, so any performance improvements with paging VRAM<->SYSRAM would be a benefit. Particularly as LDDM-Basic has CPU-based context switching, it's not until LDDM-Advanced that the GPU can take over with hardware context switching.

It'll be debateable as to whether it matters much for games - the desktop manager is likely to be sensible enough to run and hide whilst a game makes the GPU cry.

I'm not 100% sure, but the big win with PCIe is with it's read-back performance. AGP plain sucks at that - fast writing, crap reading. I can imagine it'd be fairly easy to bias a context switching system to favour writing and have limited/no readback.

Jack

 

[Diplo]

The usefulness of PCI Express is obvious: It gives motherboard and hardware manufacturers the chance to make lots of money by making all our old hardware redundant so we are forced to upgrade. I guess they've taken a leaf out of the music industry, in this respect...

 

[IgnorancePersonified]

I just hope more PCIex1 and 4 cards come on the market. All sorts any sorts. PCI slots are still on current microITX mobo's and some include mini PCI slots. Stupid waste of space to me. Even if gfx cards were PCIex8 or even 4. If high end don't need the extra bandwidth now then its over kill for the short term.

 

[Diplo]

I just hope more PCIex1 and 4 cards come on the market.

I can't actually recall seeing any products that use the x1 format and precious little that uses the others (apart from video cards).