CPU or GPU bottlenecking in next-gen engines...

[jonathan_phang]

Hello all,

After swearing blind that I was going to do an upgrade to C2D after the alleged price cuts later this month, I started totting up the prices and it'll cost somewhere in the region of £600-£700 quid to get all I need. Thats a smidge over what I comfortably want to pay, but does involve CPU/GPU/RAM, all the major pieces really.

Anyway, that made me have a look at the upgrade path available for the moment (Take a look at the rig on the left) and my other major option is to just get a dual core AMD whether it be opteron or X2, followed by a decent GPU in a couple of months (say a 8800GTS class one)

This next planned upgrade is all about letting me be able to play the raft of next gen games that will be coming out such as Crysis, UT2007 and the games based on those licenseable engines. My question at the end of this (Yes, there IS one!!!) is to ask opinions on whether or not the CPU will really be utilised much at all in the upcoming generation of games, or whether or not spending on the DX10 GPU is going to make the majority of difference, as this may be the place where the majority of the processing will take place.

I've tried to read around on the subject on various sites and although going the C2D route at the moment would be 'better' overall, am I right in saying that the CPU would only really be the bottleneck say, if there were tons of AI in games or if I were using ultra-high resolutions. If that were the case, then the CPU wouldnt be able to 'feed' the GPU enough right? I only plan to play at relatively low resolutions, 1440x900 or at best 1680x1050 if i upgrade my monitor, so I'm starting to thing I may not need to upgrade the whole rig just yet.

I dont really do encoding that much and although i have the money available, it seems to be a bit more sensible (Hate that word...) to get a passable CPU now, and pair it with a good new GPU, at least until the dust has settled on the new AMD/Intel architectures for quad cores, to decide on who to go for the next proper upgrade. Just wondering what you experts could tell an oik like me!

Sorry for the rant - its early, and I'm fairly tired... finger just keep typing... have a good BH all!!

[NightshadowUK]

If your main aim is to be able to play next-gen games then I think you'd be right in saving money and grabbing a cheap X2 or Opteron and a 320MB 8800GTS (or waiting to see what ATi come out with).

Gaming wise, going C2D is going to have very little impact on performance. It's all about the graphics card.

[arthurleung]

It is also about how big a monitor you got
IMO High-end graphic cards are useless if you don't have a 24"+ monitor.

Do your really need a GPU with 1GB ram when 256 is enough for a 17~19" monitor

Do you really want to see a character with 100K hairs moving in a game instead of 10K?

I think there is a limit to what a monitor can show regardless of the number of pixels, and there will be a limit on how much processing power you will (ever) need.

[jonathan_phang]

It is also about how big a monitor you got

I have taken this into account in my original post (sort of) where I state the res that I have/may move to, but i kind of want to make sure that I wont be bottlenecking myself if more games become CPU dependant. The post isnt really about the GPU - going to get the same one regardles of the outcome of this thread, but its the CPU and hence the underlying components that I need info on.

I'm sure with the new engines, CPUs will be used more so for AI physics etc, but I guess the X2 is no slouch, and can be used for a while until AMD get a chance to reply with their Barcelona cores. It is still a dual core, so it should be able to utilise multi-threaded apps, although less so than C2D.

What I'm basically trying to figure out is - at lower to mid resolutions, is it more likely that the CPU will limit performance...???

[Biscuit]

Its really difficult to say how next gen games will utilize the various componants but i think its safe to say they will need more of everything

As far as C2D is concerned it can hold the ground for other componants int he system really well. My friend is running a E6400 overclocked to about 2.6 and the graphics card is an old 6600 which he has clocked the hell out of. With lower setting he can actually almost match the performance of my computer in BF2142 (until it gets into the crazy explosions etc) which does suggest that the CPU plays a huge part.

What i said above suggests that if you did move to C2D then the graphics card your running now would still be fine until you can say for definate what you will need for the DX10 games however, I personally think you should either stick with exactly what you have got or pick up a X2/FX/opteron and just wait and see exactly what happens with the ATI/Nvidia and AMD/Intel battles. At least by then you can read a definate list of what the games will actually require.

[Lucio]

I'd be inclined the say that the newer generation games will become more and more CPU intensive as the physics calculations are moved onto the spare cores of a chip.

After all, look at MS Flight Sim X, that's damned hard to run at top specification because the CPU is working so hard to run the physics calculations.

However, that said, not all game designers think like Microsoft (thank god!!), so you can hedge your bets, get 2nd best for everything but the motherboard & PSU, so if anything turns out to not suffice, then you can always sell it on and upgrade.

[Million]

I upgraded GFX first, and i'm very happy with the result. I have a paltry venice core 3000+ CPU, and at the moment 512 of RAM (i've had to RMA my normal set), but with an X1900XTX the system happily runs CoD2 in highest settings on a 21in monitor. Just anecdotal evidence, but food for thought

[prehensile]

I would say it's a balance at the moment, there isn't a clear bottleneck

[aidanjt]

I'd be inclined the say that the newer generation games will become more and more CPU intensive as the physics calculations are moved onto the spare cores of a chip.

After all, look at MS Flight Sim X, that's damned hard to run at top specification because the CPU is working so hard to run the physics calculations.

...

The two competing Physics APIs (HavokFX and PhysX) utilises available discrete hardware (GPUs and PPUs respectively) taking the load off the CPU entirely, it's more likely that the extra core utilisation will be focused on more complex AI models with an aim to shift away from expert systems as dedicated physics hardware becomes more common, real world physics calculations are even more complex than 3D rendering, so clearly the CPU was never an ideal lasting solution for physics, the massively parallel nature of GPUs are well suited for this, just look at the massive performance boost folding@home received with it's GPU cilent, or even GPU assisted video transcoding sees another huge boost in performance.

Things don't seem to be going well for Aegia though, developer uptake on PhysX doesn't seem to be going so well dispite it's API being freely available, of course they'd probably do themselves a favour if more manufacturers were producing cards and they were a lot cheaper.

[shaithis]

Well, I am pretty sure that the 8800GTX will bottleneck with any currently available CPU. I had to run my system at stocks speed recently due to a PSU issue and my performance plummeted.

Once I got a new PSU in, I started ramping my overclock back up to where it was and saw noticeable performance gains each time I pushed the CPU harder.

But with a smaller monitor and slower gfx card, you may not see that.

[kalniel]

In my opinion future games will always be GPU bottlenecked. It is always quicker to make a game look better and 'next generation' by putting more work on the GPU, and the methods for doing this are relatively well understood. The only game I can think of at the moment that is fairly well balanced is Supreme Commander, and even then you've pretty much just got to go dual core to help things out.

It always sounds bad to say something like a 8800GTX is bottlnecked by any CPU - it simply means that you're already getting insane performance and to get even higher you'd need a faster CPU. In terms of what actually affects your gaming performance, as in the minimum required to have a good game, the limitation is always more likely to be on the GPU than the CPU - ie a minimum spec GPU and recommended spec CPU combination is going to give you worse performance than a minimum spec CPU and recommended spec GPU.

[shaithis]

In my case, I was getting poor FPS with the CPU @ default speeds.......but this is at 2560x1600 resolution, so I was seriously taxing the GFX card.