SLI GTX970 + Intel i7 3770

[Rygem]

Good day,


This week I got my second GTX970 card and put it in SLI mode. I have been testing performance thoroughly with various games, 3Dmark 2013 and Heaven Benchmark.

But I noticed, while monitoring GPU usage, clock, FPS and CPU usage that in games my GPU usage is rarely 70-80+ (in most games hovering around 50-60% even 30-40 in some games) while my CPU usage is between 60% - 80% with spikes of 90%+.

The reason why I suspect a CPU or maybe a possible other bottleneck, is because de GPU load is 98-99% while running 3dMark and Heaven Benchmark at extreme/ultra quality.


My specs:

GPU: 2x MSI GTX970 gaming 4g OCed to 1418 mhz (I tested without any OC, still the same thing)

CPU: Intel Core i7 3770 3.4GHz (turbo is off)

HDD: Seagate 7200RPM 2TB

RAM: 16GB @1866MHz

PSU: Some Cooler Master 800W PSU

OS: Win 8.1 PRO 64 bit

MB: Gigabyte Z77X-D3H



It is even so bad that the load in Cities: Skylines is about 20% - 30% which causes me to get 60 fps fully zoomed out while less than 20 fps zoomed in. This shouldn't be the case with 2 cards of this level in SLI.

Skyrim with ENB enabled also 60-70% load while it should easily stress the card 99% with those demanding mods.

Farcry 4 maxed also low FPS (40-60) while 60% load etc.etc.

And the weird thing is, that the GPU load is constantly fluctuating (not steady) just like the CPU load. And I am not talking about a few percentages but about ~10% every half a second or less.


So what is the cause of this? defective cards? CPU bottleneck? something else?

I am really at a loss. If I get 60 + FPS at some of these demanding games with just 50-60 % load I could get really smooth frame rates (I have a 144Hz monitor) if my GPU's would work at 99% power.

an example:
http://postimg.org/image/wxj147fyv/
http://postimg.org/image/6qyp60din/

Thanks for reading,



Rygem.

 

[INSTG8R]

Why have you disabled the Turbo?

 

[rtwjunkie]

I'm trying to remember from the last time I SLI'd, but when you use two GPU's, your load should be lower on the GPU. The CPU load will be higher because it is "feeding" two GPU's. As for Cities, that is a demanding CPU game. Skyrim, even with ENB and other texture mods is not going to tax two 970's all that much. Heaven is a decidedly GPU-centric benchmark. That's where most of your load will be.

 

[RCoon]

Some games have FPS caps, some games you may have VSync turned on, and more importantly, some games are CPU bound rather than GPU bound.

Especially Cities: Skylines. You won't see much GPU usage because that title is almost primarily CPU orientated. If you want better performance in that, you need to make your CPU go a little faster (turn on turbo, overclock).

 

[rtwjunkie]

As @RCoon said, you can overclock that 3770. It will do 3.7GHz with all 4 cores fulltime if you want. And you can go even higher if you are willing to drop some cores, because that's what happens starting with 3.8GHz.

 

[azngreentea01]

i dont think the problem lie with i7 3770, that cpu is not going to bottleneck your graphic cards. I cant see picture, at work
May be something wrong with drivers, uninstall and reinstall, make sure you check sli enable in graphic cards properties.

ALso, turn on turbo for your cpu > imo

 

[Rygem]

Thank you all for the quick and helpful replies.
I disabled my OC because someone on another forum told me to remove the OC and test if that resolved the problem. I was running at stable @4.3 ghz earlier, so I can do that again.

I'm trying to remember from the last time I SLI'd, but when you use two GPU's, your load should be lower on the GPU. The CPU load will be higher because it is "feeding" two GPU's. As for Cities, that is a demanding CPU game. Skyrim, even with ENB and other texture mods is not going to tax two 970's all that much. Heaven is a decidedly GPU-centric benchmark. That's where most of your load will be.

Thank you for replying. I understand that the load is balanced between the two cards, so why doest it sometimes run below 40 FPS (Skyrim) and below 60 (Far Cry 4) even if my cards AND CPU aren't stressed at all. That is the strange thing.

I could call it poor optimization, but before I got my SLI setup the single GTX970 would be stressed 90%+ even with low or highFPS. My point is that if it is not demanding, if it shouldn't be a problem for my graphics card OR CPU, (not talking about skylines anymore) why do I still get low performance?

 

[rtwjunkie]

That is strange, because you should easily be near 60fps on Skyrim, even on one GPU. But the "sometimes" is normal, based on what is being rendered. What's your resolution? I may have missed it, but didn't see it anywhere.

 

[azngreentea01]

For Skyrim, with out any ENB mods, they have vysnc on, because with out it you can not play, it will be at 60 fps at all time, i believe. For Farcry 4 on EXTREME Nvidia setting - you should get around 50-110 fps depend on the area and actions if you are using 1080p monitor,.

http://www.overclock.net/content/type/61/id/2254216/

ALso go to this thread, find people test score on unigine heaven 4.0 and do some testing.
http://www.techpowerup.com/forums/threads/unigine-heaven-4-0-benchmark-scores.198888/

 

[Rygem]

For Skyrim, with out any ENB mods, they have vysnc on, because with out it you can not play, it will be at 60 fps at all time, i believe. For Farcry 4 on EXTREME Nvidia setting - you should get around 50-110 fps depend on the area and actions if you are using 1080p monitor,.

http://www.overclock.net/content/type/61/id/2254216/

ALso go to this thread, find people test score on unigine heaven 4.0 and do some testing.
http://www.techpowerup.com/forums/threads/unigine-heaven-4-0-benchmark-scores.198888/

My Heaven score:

http://postimg.org/image/4jh6k0xhf/

Ignore the CPU clock it was oced at 4.3 ghz
As you can see the gpu's are working just fine. It is kind of funny how games that used to perform twice as good as Heaven are now performing worse.

 

[Hawkstream]

Why don't you have an SSD? A 7200RPM drive is a GIANT bottleneck for everything else.

 

[Devon68]

Why don't you have an SSD? A 7200RPM drive is a GIANT bottleneck for everything else.

While it might be a bottleneck for loading times it should not affect FPS in any way.

 

[GreiverBlade]

That is strange, because you should easily be near 60fps on Skyrim, even on one GPU. But the "sometimes" is normal, based on what is being rendered. What's your resolution? I may have missed it, but didn't see it anywhere.

yep strange indeed

Skyrim with a ENB (and custom preset on the infamous RealVision on 0.266d) with 135 mods loaded (counting high res and static mesh improvement mod, some weather mod plus some high poly and having 10 follower around in a town or in a fight, Dragon or heavy populated one) 59.9fps constant on a 4690K and a single 290. tho it's at 1080p (and with vsync hardcap, i don't like tearing ... )

Why don't you have an SSD? A 7200RPM drive is a GIANT bottleneck for everything else.

not really i have a SSD for my OS but my games are on a Toshiba DT01ACA100 7.2k rpm, loading time indeed but FPS once loaded: nope.

also SLI scalability isn't ... what's the word already? oh well : single GPU over SLI/CFX anytime (tho i planed to go CFX 290 for fun before i switch gen)

 

[newtekie1]

Even in Heaven there is an issue, the minimum FPS shouldn't be 9FPS.

 

[GreiverBlade]

Even in Heaven there is an issue, the minimum FPS shouldn't be 9FPS.

yep that's strange, my heaven run are also on the HDD and i get that:


sidenote... maybe it's the dreaded 3.5+0.5gb symptome??? (joking but ... )

 

[kn00tcn]

you know you can put your CPU usage numbers into your afterburner so you dont need multiple screenshots

cities skylines 20fps with low usage... that one is interesting, i would want to test single gpu to see if the usage is also low (or the same as adding the 2 gpus)

 

[MxPhenom 216]

Thank you all for the quick and helpful replies.
I disabled my OC because someone on another forum told me to remove the OC and test if that resolved the problem. I was running at stable @4.3 ghz earlier, so I can do that again.



Thank you for replying. I understand that the load is balanced between the two cards, so why doest it sometimes run below 40 FPS (Skyrim) and below 60 (Far Cry 4) even if my cards AND CPU aren't stressed at all. That is the strange thing.

I could call it poor optimization, but before I got my SLI setup the single GTX970 would be stressed 90%+ even with low or highFPS. My point is that if it is not demanding, if it shouldn't be a problem for my graphics card OR CPU, (not talking about skylines anymore) why do I still get low performance?

Skyrim does not support SLI. it does not scale whatsoever with more than one card, unless you are playing at 1600p or 4k.

 

[Rygem]

yep that's strange, my heaven run are also on the HDD and i get that:
View attachment 64826

sidenote... maybe it's the dreaded 3.5+0.5gb symptome??? (joking but ... )

Well my fps just stutters at the start of loading in items and textures, so that is that cause of the 9fps. but most of the time it was 100+ FPS. I get this a lot in some games.

cities skylines 20fps with low usage... that one is interesting, i would want to test single gpu to see if the usage is also low (or the same as adding the 2 gpus)

The thing that I noticed in the measurements with all these games, is that whenever the fps is high the usage is high and when the fps is low the usage is low. It is like something is holding it back whenever the game becomes more demanding.

The same with Diablo3. It doesn't drop below 100 fps but still most of the time the load is 20-40% with sometimes 180 fps with 50-60% load and then suddenly a few seconds where the load is 90+% with 260 + FPS. It doesn't make sense at all.

Could this be some BIOS setting?

B.T.W.... I must tell you all that Skyrim runs pretty fine now, i did some .ini tweaking/optimizing now it's pretty steady 60-90 + with some dips here and there but pretty fine. At least a lot better than with single card where I couldn't get it higher than 30 fps most of the time.

 

[P4-630]

Also don't use Fraps, that is IF you used that as fps counter, it causes fps drops

 

[Rygem]

Also don't use Fraps, that is IF you used that as fps counter, it causes fps drops

I use RivaTuner

 

[newtekie1]

Can you post GPUz screenshots for both GPUs and a CPUz screenshot for you processor?

 

[Rygem]

Can you post GPUz screenshots for both GPUs and a CPUz screenshot for you processor?

Do you want the screenshots when in game or when idle.

 

[newtekie1]

Doesn't matter. They can be idle.

 

[Rygem]

CPU + GPU1:
http://postimg.org/image/yzxw5ksqd/
GPU2:
http://postimg.org/image/4mgg8108l/

 

[newtekie1]

When you put load on the CPU does it actually go up to the 4.3GHz?