random FPS drops after a few hours (SLI GTX 680)

[Sasso]

hey there,

so just bough myself a second gtx 680 (evga superclocked 2gb model) and got them in SLI and it is sweeettttttt!!!!!

however........ I have noticed..... been playing lots and lots of far cry 3 the past few days and after playing for about 4-5 hours I start to get random FPS drops/ stutters every 2-3 seconds.

up until a good few hours in it will be rock steady, but then I will start to notice a visible stutter every few steps I take. now if i close the game and reopen, the problem persists. however, if I restart my PC it's fine again for many more hours.

It will drop (for example) from say 120fps down to 95-100 and the go straight back up again. I have had gpu monitor open and I think the GPU usage on both cards drops by about 10-15% at the point of stutter and then back up again.....when first loading up the game and on the most part both GPUs are running 90%+ usually 94-99% but when the stuttering occurs then drop down to about 75-85 ish and then momentarily down to about 65%.

has anyone else experienced a similar problem? currently running 310.70 WHQL drivers.

rest of system:
i7 [email protected] (HT on)
16gb 1600mhz ram
z77 sabertooth board
silverstone 1000w psu
game is on a sata 3 ssd


any ideas? experiences? solutions? suggestions?

 

[Bromhead]

Sounds like throttling to me, especially with an sli set up... I would definitely start by checking the temps of your cpu and gpu, I think it's likely they are overheating and reducing performance to cool down

 

[Rroff]

Does it happen with other games or just Farcry 3? from what I've heard/seen people post the game seems to be a bit problematic on performance/driver compatibility in general.

 

[Sasso]

GPU temps are 70-84 oC, CPU usuage is around 50% so doubt that is over heating. also if i restart my pc it is fine again for say about 5 hours... so if it was overheating i think it would throttle allot sooner as only takes about 1 min to get back into the game from closing and restart.

well i've only really been playing FC3 for extended periods of time so I've only seen it occur after hours of playing that. but if i do launch another game of FC3 after about 10 mins it still does it, and i think i could see it in bf3 if i load that up after too (not 100% sure on that one tho).

 

[Bromhead]

I would give a few other games a go, see if you can stress the machine and produce the results in different games, may help to narrow it down. I guess the mystery is why it happens after 5 hours...

 

[Sasso]

yea i'll have to have a bf3 marathon or something tomorrow. I'm just wondering if it's something in the game that possibly causes a bug with the drivers.... hence the restart fixing it. tis a curious one for sure....

 

[PCZ]

It is most likely a software problem.
Some sort of memory/resource leak.

There is something else you can try.
To rule out any potential problem with pci-e gen 3 signalling.

BIOS
Advanced
Sytem Agent Configuration
NB PCIe Configuration
PCIEX16_1 Link Speed set to gen 2
PCIEX16_2 Link Speed set to gen 2

Most likely there set to auto and will negotiate gen 3 with the 680's.

 

[Sasso]

when you say software problem, would you be referring to the nvidia drivers/sli profiles etc, or far cry 3? or something else?

and i could try that. going to run gpu-z cpu-z realemp and the asus monitor and track all temps just incase. only one that i saw could be an issue could be the Vcore temp (VRMs i issume) but like using IBT they only got to about 53oC.. nothing too hot...

so set gen 2 . 5 hours of far cry then a bf3 marathon xD well there goes my day hahaha oh poor me forced to play games... hehehe

 

[PCZ]

Software problem could be drivers or game engine.
What about you play 5 hrs of Skyrim for a bit of variety.

Note:
I am currently using a pair of 680's in a Z77 ASUS pro but have not done any marathon gaming sessions of late,

 

[Sasso]

don't currently have it installed xD i'll try that gen 2 thing as a starting point i think as i think another 5 hours or so and i'll have completed the story line in FC3

 

[Sasso]

UPDATE:

right i tried with gen-2. but i completed fc3 after only about 3 hours and couldn't be arsed running about for another 3 as i've don't pretty much every side mission too but i did notice the gpu usage had reduced but couldn't see any spikes as such, there were little ones in the gpu usage but not noticeable in fps... well not as bad as it was before.

so well there is definitely a reduction in gpu usage the longer it's used it seems...