Problem overclocking 6950

[MercilessPandaBear]

Hi everyone,

I have an XFX 6950 2GB (the non-reference version), and am having some difficultly overclocking it.

I tried MSI AB, but couldn't get it to do unofficial overclocking, so I tried Sapphire Trixx, which seemed to work well.

However, once my card hits 80*C, it starts artifacting. I have messed around with it, and it doesn't seem to be clock or voltage related, it just artifacts the second it hits 80 degrees. So my question is- Is there any throttling that could be occuring because of this temp?

I thought these cards were good for 95* stable. I am currently trying 927 mHz on the core at 1.24v. I am in GPUz, and am not seeing any throttling on the core speed, voltage, amps, memory, nothing.

Thank you for your help!
Ben

 

[spagalicious]

That core voltage definitely seems very high. I have mine at 1.175 with unlocked shaders @ 910/1400 idle at 38*. Never above 70* gaming. I would say any throttling would definitely be due to those high temps.

 

[MercilessPandaBear]

Thanks for the quick reply.

I was under the impression that this was a reasonable voltage and temp for the card. I thought max safe voltage was 1.3 and max safe temp was 95.

That 80* is also in ATItool, in gaming it is lower.

Is there any way to disable throttling?

 

[spagalicious]

I'm not the biggest overclocker but I would say if temps are that high, it would be the voltage. Is that the only voltage you could achieve over 900mhz core? Have you tried something like a 1.18?

 

[MercilessPandaBear]

I thought these temps werent bad. Max is 95* right?

 

[spagalicious]

Yeah theoretically but is there a reason you have the voltage so high? Were you unable to achieve a substantial overclock with lower voltage? The voltage may be causing the artifacting. I personally wouldn't be comfortable with those temps. As for the safe zones, all cards are created differently so maybe you got one that can't handle as high of overclocks? I'm not sure. I would definitely back it down to see if the problems still persist. The few fps you would gain from a 900 and 927 overclock would be minimal and not worth the heat and artifact problems.

 

[MercilessPandaBear]

Tried Furmark.

Furmark begins throttling core speed and load when temps hit 78*.

Load jumps from 0 to 100%, and core jumps from 500 to 915.

At stock voltage.

So throttling is the issue. I just don't know why it is doing it. 6950's don't throttle until 100*.

 

[bystander]

You can unlock MSI afterburners by altering it's .ini file.
This might not be the most up to date syntax, I know the beta has different syntax: http://www.overclock.net/t/677696/how-to-unlock-msi-afterburner
This is the directions for the beta version: http://forums.overclockersclub.com/index.php?showtopic=182403

 

[MercilessPandaBear]

So Trixx is the cause of the throttling?