New CPU or already GPU limited?

sir doris

Regular
Hi,
I'm thinking of upgrading my CPU/ Motherboard/ RAM/ SoundCard but i'm not sure if my system is already GPU bound so the upgrade will have no effect on gaming?

The extra CPU power would be nice for other things also but it's mostly for gaming.

My current system is:
A64 3500+ (NewCastle core, I think or whichever the big old one was ;) )
ASUS A8N 32 SLI
4 x 512MB CAS2 DDR-400
nVidia 7950 GX2 (slightly overclocked)
Philips Acoustic Edge (Thunderbird chipset)
Dell 2407WFP

Possible upgrade:
Core 2 Duo E6600
2 x 1Gb CAS4 DDR-800 (PC-6400)
Abit AB9 Pro
X-Fi XtremeMusic/ XtremeGamer
Gigabyte Galaxy II water cooling kit (Maybe)

The reason I think I might already be GPU limited is because I game at my monitors native res (1200 x1920) which stutters now and then. However two of my games; rFactor and GTLegends which do not seem to be that graphically demanding suffer from stuttering quite often and bad framerates with lots on cars onscreen. While playing on high detail levels the games was almost unplayable (~30fps) but even when disabling AA and droping the res things didn't improve much, it was only when I lowered the detail levels that things became better, then increasing the res made little to no difference. So now i'm running mid to high graphical details at 1200 x 1920 with 2xAA and 8x AF and getting 40-60 fps (V Sync=on), however in places the fps can b as low as 20fps (in these circumstances lowering the res to 1080x1650 and turning AA off made no difference).

All the above is with the nVidia drivers set to the default quality setting and all the optomisations enabled (triliner/ anso/ etc.).

Basically I never get near benchmark scores for the GX2, so i'm trinking my main system is holding everything back a bit? Also my sound card is old and missbehaves on some games, so an xFi is on the cards.

If I upgrade I intend to overclock it (hoping for 2.8-3.0 GHz nothing insane) and I have a Coolermaster ATSC chassis so homefully that should help it :)

Sorry for the long post, I bet even now I've missed things out ;)

Any advice welcome.
 
One of your big issues is the fact that you're using four DIMMs of memory. This is a known killer on older revisions of A64s. In fact your memory performance is actually being hurt pretty bad right now from my own past experiences.

I'd personally recommend you go with the new processor and the other parts you listed. Except you should NOT go with that abit motherboard. Its very lacking in a lot of areas compared to other motherboards that use the P965 chipset. I'd recommend you go with a Gigabyte 965P-S3 or better the DS3.

*Can someone confirm if a motherboard must support SLI for the 7950GX2 to work?
 
Hmm, I'd look around and try to find if anyone has used the Gigabyte I listed with a GX2. If that abit is compatible then the Gigabyte should, but I do not want to confirm it 100%.
 
One of your big issues is the fact that you're using four DIMMs of memory. This is a known killer on older revisions of A64s. In fact your memory performance is actually being hurt pretty bad right now from my own past experiences.

The updated memory controller didnt attribute to adding much performance to games though skrying. You'd be lucky to see a 5% difference across the board in games, especially newer GPU limited ones on a newer revision. The difference between 2T and 1T and its impact in games is trivial at best.

i'm not sure if my system is already GPU bound so the upgrade will have no effect on gaming?

Well you can tell whats going on in the games you play pretty easily. If you can increase AA and AF with relatively little impact on the framerate, be it bad or good already, then you are largly limited by the processor. If on the other hand things like AA are causing rather substantial impacts in performance, then you're GPU limited. On newer games like FEAR and Oblivion and even Doom 3 engine games at your monitors native res you're going to be GPU limited 90% of the time though.

Basically every review i've seen of Conroe being used in a real gaming scenario, meaning AA and a moderatly high res and settings, i've seen all versions, be it Extreme editions to the cheapo 1.8GHz model, fall in line with eachother, and the AMD processors hang pretty close in there (+/- 5-10%). I seriously wish they would stop showing so many low res or old game benchmarks because it is misleading as far as what the consumer can expect.

Your native res is right up there, and you will be using AA/AF as well as max settings, so you're putting quite a strain on your GPU and removing alot of attention from your processor in most cases already so i'd feel pretty confident in saying that you problably wont see some huge difference in the upgrade unless you fork out cash for an 8800GTX SLI setup. Games like rFactor and GTLegends problably dont even use SLI that effectively so its quite probable its running on a single card which is causing some of your performance issues.

That said your general performance will improve obviously though as Core 2 Duo really is substantially faster, but in most gaming situations you will problably be a little dissapointed since at your normal settings you wont see anywhere near the 20-40% improvement that most CPU limited, low res, low setting benchmarks show.

If you do end up upgrading though i'd seriously suggest getting an Nvidia 680i chipset based motherboard for core 2 duo over any of the intel chipsets right now unless you plan on running crossfire in the not so distant future. Theres Asus, eVGA, ECS and Biostar motherboards shipping right now with others like DFI and Abit on the way for early 2007. The chipset is every bit as good if not better as well as having a little bit more room for some future upgrades like SLI, hardware driven physics and touting that its ready for intels next iteration of core 2 duo based 1333FSB driven processors.

Heres a couple that did some high res/settings gaming just for example showing what happens in real world situations on at least SC and Quake4, two games that are used to show differences in CPU power when they're settings/res are reduced heavily. Increased to something closer to what you'll be playing at and the advantage is all but gone. Despite these using higher end AMD parts as well, throwing in the cheaper processors would result in essentially the same numbers because of the lack of the processors impact at those settings.

http://www.hexus.net/content/item.php?item=5692&page=3
http://www.hexus.net/content/item.php?item=7348&page=8
 
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If you want a gamer machine, you might want to spend most of your money on the video card (I would wait for DX10 hardware though).
 
Thanks for the replies :)

While I realise I must be getting close to being GPU limited, and looking at those benchmarks between the Core2 and the FX-62 I can see there isn't much in it, both those systems are considerably better then mine and use fast DDR2 where as I'm using 4 sticks of DDR at T2 timings. I guess i'm hoping that this is adding some latency into the whole thing, together with my ancient sound card sucking even more CPU cycles out of the system...

Re. DX10, i'm not sure a 8800GTX would be a worthwhile upgrade with my current system, as it is FEAR requires medium settings for physics and CPU stuff and even then it doesn't run that well, even at lower res. While my brother has a E6600 with 2Gb DDR2-800 and it runs really well with everything on full.

thanks again, BTW still not decided ;)
 
well like i said, if they threw in even the low end stuff it would all be hanging together. Memory latency damages performance on Intel systems because it effects that FSB which is so key, it really doesnt impact AMD based computers by a noticeable amount. I've run enough T1/T2 tests on my computer to know, and the conclusion is its about 3-5% at most and a lot of times nothing at all.


skim through these

http://www.driverheaven.net/reviews/core2review/index.htm

seem to be the best collection of high quality processor benchmarks, again though i have to stress the fact that just because higher end processors are only listed doesnt mean that if low-mid end parts were there too they'd be destroyed, its actually the opposite effect. In FEAR for instance the game is badly GPU limited at those settings so you'd have a 1.86 core 2 or a 2.2 GHz Athlon X2 sticking right behind those high end processors literally neck and neck. Thats the entire point to a GPU limit. You can actually see this yourself where HL2 or nets a huge boost with Core 2 while FEAR or Prey at those high settings (again these are games that primarily show the bonus of CPU power on their low settings) dont do much of anything.


If you're only able to play FEAR on its medium settings you may want to check into the drivers and making sure SLI is working. Forcing all the 'CPU' effects on shouldnt do much of anything at that res. FEAR of course does use dual core processors as well (though i doubt its to any great effect).
 
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