Overclocked Intel Core i5 2500k @4.3 GHz bottlenecking GTX 460(x2) SLI in Crysis 3?

bystander123

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Hey guys, when I bought the i5 2500k for a high price I thought I wouldn't have to worry about CPU bottleneck for a long time. Then, managed to crank it to a decent and stable 4.3 GHz (from stock 3.3) by overclocking. That gave me the confidence to think "well, I am pretty much on par with stock i7 3700s or even better!". I had a GTX 460 1 GB. So, I threw another GTX 460 into the pc so the GTX SLi couple can be a decent "GPU partner" with the beasty i5 CPU. Recently, now that I tried to play crysis 3 at high settings, I am a little surprised. The OCed 4.3 GHZ Core i5 2500k seems to be actually bottlenecking this simple SLi setup of GTX 460s. The first intro level was all buttery smooth at constant 60 fps (using vsync). But, on the second level right where you come out to a graphically heavy open environment with grassy fields and rough terrain, things kind of start to get not as "smooth".
There the fps were in the 40s (43-46), infrequently dropping down to 30.

As usual, my initial thoughts were "ok, maybe the GTX 460s aren't quite being able to pull it". I play at 1600x900. Just to confirm my thoughts I lowered the resolution to 1366x766. I saw absolutely no increase in fps, then lowered the res. all the way down to 1024x768. Still, almost the same fps as I would get at 1600x900. I was like "what in the world??! Is my beloved OCed 4.3 ghz i5 2500k bottlenecking my simple stupid 460s?" I was astounded. So, I brought up my OC tools (MSI afterburner etc etc). I ran them in the background as I was playing crysis 3. CPU usage is 70% to 80% across all cores, the gpu usage - thats the part that shocked me. GPU1 is 98% but GPU2 is only 7-10%, are you kidding me? Just to make sure SLi is working properly, I turned the SLi visual indicator on from nvidia panel. Yep, its working. Tweaked nvidia profile and forced "SLi" on crysis 3, got GPU1 45-50%, GPU2 45-50%. So, the Sli is working but the gpus aren't getting enough work load during gameplay. That has only one conclusion "the cpu is bottlenecking the gpus!!".

Seriously? Does Crysis 3 really put so much pressure on the cpu? If it causes an overclocked i5 2500k to bottleneck, it would surely bottleneck other i7 3700 series CPUs at stock clocks. What if I had GTX 680? I would probably have to order a $1000 CPU from intel just to make the CPU stand up to the GPU to get 60 fps? This is really a poor coding on part of the developers. What do you guys think? Am I doing something wrong?
 

Inferno1217

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Your CPU is fine it's your GPU's that are too old and under powered for a modern game like Crysis 3.
 

bystander123

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If my gpus are too old, then why is only 45% (together from two cards) of their power being used in the game? And, why is lowering the resolution from 1600x900 down to 1024x768 giving no performance impact? If its the gpu, lowering resolution should give a considerable fps boost in any situation.
 
I read earlier that you were using v-sync. If you are looking at a not demanding scene with v-sync on your fps will be capped at your refresh rate, usually 60 fps, no matter what resolution you use or graphics setting it is set to.

Try turning off v-sync so that we can get an actual representation of your fps.

Your CPU is a contributing factor, although the GPU is what is keeping you from acceptable FPS.

http://www.tomshardware.com/reviews/crysis-3-performance-benchmark-gaming,3451-8.html



 

bystander123

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Well, it turns out, tomshardware's benchmark article on cpus in crysis 3 has the answer.

Our benchmark sequence does have that taxing bottleneck at the end of the run. But no matter how you process the data, processor performance is going to be an important consideration in Crysis 3. We can't recommend anything less than a Core i5 to gamers building a PC capable of handling this game, and serious enthusiasts will want a Core i7. Crysis 3 appears to be one of those rare games optimized for multi-core processors, as evidenced by the six-core Sandy Bridge-E's strong result compared to quad-core Ivy Bridge.
http://www.tomshardware.com/reviews/crysis-3-performance-benchmark-gaming,3451-8.html

In the benchmark, a Core i5 3550 IB is bottlenecking GTX 680 down to an average fps in the 40s. (min 31, avg 49, I would think in an intensive grassy level like the one I was talking about above, the avg fps shouldn't be 49 but less in the range of 43- 46). A six core i7 3960X gives a significant boost of about 20 fps over the i5 ivy-bridge and takes fps to the 60s.

My GTX 460 SLi is more than enough to handle games at a decent 1600x900, cos I dont game at 1920x1080 or greater resolution. In all other recent games, as in bioshock infinite, far cry etc etc I never got a single fps drop from the vsynced 60 fps. In fact, crysis 3 is the first game in a long time in which I couldn't keep a constant 60 fps and that is due to the i5 cpu not the gpus, as it seems.

Crysis 3 appears to be one of those rare games optimized for multi-core processors
I would rather say one of the "stupid" rare games, how many of us really have $1200 hexacore intel cpus?
 

bystander123

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Turning off vsync does not improve fps in those grassy areas at all. I know vsync caps fps at 60. Without vsync, fps goes as high up as 95 in the first level, but in the second grassy level it stays in the 40s (43-47).
 

bystander123

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Not necessarily, as far as I know. It depends on how well the game is programmed to utilize the cores. In my situation, neither the cpu nor the gpus are getting 100% load. The cpu is getting 70% load (infrequently rising to 80%) and the gpus together are getting only 50% load (Gpu1 45-50%, gpu2 45-50% when forced sli, in normal sli mode - gpu1 98%, gpu2 7-10%). Why isn't the cpu getting 100% load, why aren't the gpus getting more than 50% load.

My mobo is gigabyte z68x, what does mobo have to do in this? Mobo doesn't play a good role in determining fps unless its a shit mobo. My gigabyte is a classy decent z68 chip.
 
D

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2 x GTX 460s perform about the same as a GTX 480. Crysis 3 like the first game when it was released, almost can't be maxed on today's existing hardware. Hell Crysis came out in 2007 and is still used in benchmarks. The 460 was a great card and I am still running one but in 'next gen' games it's not able to keep up. Crysis 3 is such a beast that HardOCP was barely able to max it with an i7 3770k at 4.8Ghz and 3 x GTX Titans in Sli. Now that was at very high resolutions but even with $3000 worth of graphics cards the game was not playable maxed out.

http://www.hardocp.com/article/2013/04/22/nvidia_geforce_gtx_titan_3way_sli_review#.UXXIKp3D-00

So you have very good hardware but it will be years before you can you can expect to max Crysis 3 on an average system. I would imaging the 1GB of VRAM is holding you back even at 1600 x 900.
 

ihog

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Well, is the coding of the game something the users of Tom's Hardware can help you with? I'm trying to deduce a problem we can help you fix.

I asked about the mobo, because some mobos have problems with SLI/Crossfire, or their PCIe lanes drop down below x8 in SLI.
 

bystander123

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First and foremost, I am not using a very high res for gameplay, so graphics card should not be the problem here. Actually, 2 gtx 460s can beat a GTX 580, the pair will easily crush a 480 by a great margin.
http://www.hardocp.com/article/2010/12/02/geforce_gtx_580_vs_460_1gb_sli/2#.UXXLTrWG3EI

However, I am not worried about that, as I said my resolution is a mediocre 1600x900, gtx 460 (superclocked) Sli aren't a problem. With all this said, I still think I have a problem here. My cpu is not 100%, its mostly 70%. And, my gpus are far from 100%, they are barely 50% (both when working together in SLI). Neither cpu nor gpu is getting bottlenecked, then what the heck is? The question is, what is causing the hold-back? Is it necessary for your cpu to get 100% usage in order for it to be a bottleneck? Can it still be a bottleneck with 70% cpu usage? can someone verify?
 

bystander123

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The coding part was my speculation, I could be wrong. I am still trying to figure out if the problem I have is a genuine problem or "thats the way the game is designed and there is nothing I can do".

At this point, I want to reiterate -
My cpu is not 100%, its mostly 70%. And, my gpus are far from 100%, they are barely 50% (both when working together in SLI). Neither cpu nor gpu is getting bottlenecked, then what the heck is? The question is, what is causing the hold-back? Is it necessary for your cpu to get 100% usage in order for it to be a bottleneck? Can it still be a bottleneck with 70% cpu usage? can someone verify?