I thought my GPU O/C was stable

[Born_2_Kill_83]

As some of you know I have a CF7970 GHZ setup, I've managed to get 1150/1700 @ 1.263v in 3DMark and Heaven stable running on loops no problems. Max temp 84c (Auto fans).
I had artifacts with 1175 core so I think I hit my limit at that.

I then tried these clocks in Company of Heroes 2 with no problems.

But when I load Crysis 3 I get BSOD during hard action parts of the game and other CTD.

So I backed off my O/C to 1125/1600 @ 1.250 (another stable O/C in 3DMark and Heaven), and yet again BSOD and other random crashes.

Currently patching Crysis to 1.3 but Im not hopeful. I really want these cards stable at 1125/1600 ready for BF4.

Using afterburner and +20% power limit, any ideas?

 

[Drangueos]

did you try 1100mhz?

I have 2x 7950 and they need 1.25v to 1100mhz and 1.3v to 1150mhz.

I don't think you will notice any big drop of performance from 1150 to 1100mhz, but your temperature will drop for sure and maybe it will be stable.

 

[Born_2_Kill_83]

Ok will try that later, maybe it just need more juice...

 

[Born_2_Kill_83]

Also Ive noticed full screen Furmark, take my cards into the 90c's even on standard clocks.

And there was a time in Crysis where the temps went into the 90's although for most of the time it stopped around 85c

 

[Jony27]

I thought my OC was stable too after running heaven/valley with no problems, loaded up DOTA 2 which isnt the most demanding game and it crashes half way trough the game...

Also, I advise the use of Furmark, I have heard bad stuff

And try making a xustom fan profile to deal with the heat issues.

 

[Drangueos]

Heaven or Valley are not a good stability test...
I can run my cards @1180/1800 on them, but cannot run any game with this clocks

Crysis 3 on the other hand is a good stability test and 3dmark vantage as well.

 

[Drangueos]

Furmark just makes your card hot, not a good test at all... I would use it just to check temperatures in a hurry, if not Just playing Crysis 3 will do the job with less risk.

 

[PorkPieCat]

Benchmark tools give me at least 75mhz more on core, with 75mv less for "stability". I can stably run Heaven for 2 hours and crash in actual games (most quickly in Cryengine titles) until I've SIGNIFICANTLY lowered clocks and increased voltage. I would test your OC again from scratch using one of the Crysis benchmark tools. Some people think the Crysis games are too harsh on overclocks but in my experience that's not true. Other games eventually crash too at anything unstable for Crysis - just after many more hours. Benches don't reveal unstable OCs, and this is true of 3Dmark11, Fire Strike, AMD Leo demo, Unigine Heaven and Valley, and so on - at least in my experience.

 

[Marine-RX179]

As some of you know I have a CF7970 GHZ setup, I've managed to get 1150/1700 @ 1.263v in 3DMark and Heaven stable running on loops no problems. Max temp 84c (Auto fans).
I had artifacts with 1175 core so I think I hit my limit at that.

I then tried these clocks in Company of Heroes 2 with no problems.

But when I load Crysis 3 I get BSOD during hard action parts of the game and other CTD.

So I backed off my O/C to 1125/1600 @ 1.250 (another stable O/C in 3DMark and Heaven), and yet again BSOD and other random crashes.

Currently patching Crysis to 1.3 but Im not hopeful. I really want these cards stable at 1125/1600 ready for BF4.

Using afterburner and +20% power limit, any ideas?

Heaven is good for stability test, so long as you use it in the way of finding the the right voltage to get it "just enough" to stable in the bench, and then drop 50MHz on the core and 100MHz on the memory for actual games it should be fine.

So keep your original 1.263v but drop the overclock down to 1125/1600, while not drop the voltage down to 1.250 may be?

Also, demanding games tends to HATE memory being overclocked too high and can easily lead to BSOD/crashes.

 

[BluD]

Some games seem to be a lot twitchier than others, I use these games for testing overclocks rather than benchmarks. I can run heaven at 1320 MHz but crysis is only stable up to 1290.

 

[Born_2_Kill_83]

Heaven is good for stability test, so long as you use it in the way of finding the the right voltage to get it "just enough" to stable in the bench, and then drop 50MHz on the core and 100MHz on the memory for actual games it should be fine.

So keep your original 1.263v but drop the overclock down to 1125/1600, while not drop the voltage down to 1.250 may be?

Also, demanding games tends to HATE memory being overclocked too high and can easily lead to BSOD/crashes.

I hit the wall on Heaven @ 1175core and 1725 Memory, So I did as you said and backed off 50 core and 100 memory down to 1125 and 1600 but I also dropped the 1.263v down to 1.250v, this is when I got the crash, I then played Crysis 3 for 20 minutes at 1.263v again without any problems, my other overclock made the game crash in 5-10mins. Maybe I just need to keep the volts the same but wont this create more heat as it does in O/Cing a CPU? Or is it the higher core speeds that create the heat

 

[Born_2_Kill_83]

Benchmark tools give me at least 75mhz more on core, with 75mv less for "stability". I can stably run Heaven for 2 hours and crash in actual games (most quickly in Cryengine titles) until I've SIGNIFICANTLY lowered clocks and increased voltage. I would test your OC again from scratch using one of the Crysis benchmark tools. Some people think the Crysis games are too harsh on overclocks but in my experience that's not true. Other games eventually crash too at anything unstable for Crysis - just after many more hours. Benches don't reveal unstable OCs, and this is true of 3Dmark11, Fire Strike, AMD Leo demo, Unigine Heaven and Valley, and so on - at least in my experience.

Is there a Crysis 3 bench tool?

 

[Uncle Petey]

No there isn't

Have you followed these steps? http://forums.overclockers.co.uk/showthread.php?t=18431335

I recently made the statement that I reckoned 99% of 7970's should hit 1175mhz. I hope you're not in the 1% of a statistic that I made up

 

[Born_2_Kill_83]

No there isn't

Have you followed these steps? http://forums.overclockers.co.uk/showthread.php?t=18431335

I recently made the statement that I reckoned 99% of 7970's should hit 1175mhz. I hope you're not in the 1% of a statistic that I made up

I think your statement is a little off where a CF setup is concerned and I followed that O/Cing procedure to the letter. Theres not much chance of me getting these cards stable @ 1175

 

[Marine-RX179]

I hit the wall on Heaven @ 1175core and 1725 Memory, So I did as you said and backed off 50 core and 100 memory down to 1125 and 1600 but I also dropped the 1.263v down to 1.250v, this is when I got the crash, I then played Crysis 3 for 20 minutes at 1.263v again without any problems, my other overclock made the game crash in 5-10mins. Maybe I just need to keep the volts the same but wont this create more heat as it does in O/Cing a CPU? Or is it the higher core speeds that create the heat

Here's the thing...what I post in my previous post is basically saying (as others have said) actual games usually would stress the graphic card harder than Heaven, and would usually require higher voltage to stablizes the overclock. So basically if you rely on Heaven for testing stablility...when you find a settings which it would just "barely enough to stable" in it, you would want to lower the core and memory core a bit, but keep the same voltage in order to increase the odds of the overclock being stable in the actual games (alternatively if your want to keep the overclock values, you would HAVE TO bump the voltage to higher value that what is stable in heaven).

At the moment you are stable in games with 1125/1600 with 1.263v right? Although keeping this settings most probably would keep it stable, but if you really wanna finer tune it, I guess you could try either increase the core clock to 1140..or 1150 even, or lower the voltage a bit...but DO NOT do both. I would however suggest leaving the memory clock alone at 1600.

 

[Uncle Petey]

Yeah. For example, @1200mhz I need 1.219v for Heaven, but for games like BF3/Crysis3/TR the voltage needs to go up to 1.237v or the clock needs to come down a little.

 

[Born_2_Kill_83]

I havent got much headroom for extra volts, will running my cards near as makes no difference at 1.3v have an effect on its life or heat?

1125 core is a nice O/C but I would have thought a GHZ card would do more.

 

[PorkPieCat]

Is there a Crysis 3 bench tool?

I used the Cry1 tool for the max 99 runs, though I think there's a Cry2 tool you might try.

I forgot to mention but I recently tried Heaven to gauge an underclock. It passed 2 hours, after which my system crashed immediately while running a GPU accelerated video player (despite my previous experience with bench tools, I figured they should at least suffice to find the lowest possible voltage for playing videos). I just don't see the point of running a "stability" testing tool if you're going to have to later figure out a stable OC for "games" or "real use". Entirely defeats the purpose, imo. And since the Crysis bench is just a fan-made tool that cycles bits of one of the most OC revealing games over and over, it seems to make sense to use that one tool, if any. Again just to reiterate - once I use that tool, I know my stable OC, down to the individual 6mv notch, without having to guesstimate a 50mhz reduction for one game, a voltage bump for another, etc.

Also just try and keep your temps in check. Higher temps do lower lifespan (and I think volts lower lifespan by the mechanism of raising temps), so just stop when you feel uncomfortable. I like to keep temps at 70 max, though others may go higher.

 

[Tonester0011]

Crossfire for me lead to a lot lower clocks than the individual single cards could manage, my last CF7970 setup anything over 1100/1600 would instant crash.
Knock them down even further, you really wont need the extra 50mhz/25mhz, i also wouldn't personally use 1.3v for gaming on air, your VRMs will get rather toasty Unless you're really that desperate for the extra 1 or 2 FPS that tiny overclock will give

 

[mmj_uk]

It's nearly impossible to know what is and isn't stable now that apps like Furmark have been throttled, those applications use the hardware to close to their theoretical maximum.. much more than your average games which will use different parts of the GPU but in lesser ways.