HD 7970 X 2 OVERCLOCK

[dnb1337]

I have x 2 Hd 7970 Reference cards, trying to over clock them past 1125mhz they become unstable, after reading about it i don't think it's the chips that are failing me i believe it's the over current protection.

I have come to this conclusion as the whole pc power shuts down and restarts, rather than the pc just freezing.

Does anyone know the best way to over clock Crossfire Reference 7970 cards so they are stable.

 

[Deleted member 66701]

1125mhz is a good overclock - especially on xfired cards - when you xfire cards you generally hit a lower oc than if you clocked the cards singly.

Out of interest - what's your psu?

 

[dnb1337]

1125mhz is a good overclock - especially on xfired cards - when you xfire cards you generally hit a lower oc than if you clocked the cards singly.

Out of interest - what's your psu?

My Psu = http://www.overclockers.co.uk/showproduct.php?prodid=CA-151-AN&groupid=701&catid=123&subcat=

I used to have a 750 Watt psu and changed it because i to thought it may have been underpowered but still have the same problem since upgrading.

I flashed both cards with a unlocked Bios i managed to get half way through 3d mark bench mark @ 1239,mhz but that was with 1.200 v, when i increased the v to 1.299 it just crashes.

I have seen you can apparently bypass Over current protection by soldering your card which is something i am not prepared to do.

Heat isn't an issue as at full load 60% fans temps are 73 in top card and 71 in bottom, if i set fans @ 100% fans temps come down to 63 at max load but i'm happy with anything below 80

 

[BS Dave]

dude heat IS an issue if it's making the cards crash or artifact. Whether your happy with the temps has nothing to do with it

My 7970 at 1174 volts is so almost stable at 1200/1650 it's untrue. i can bench heaven/everything, but every once in a while i get polygon artifacting in BF3 and my card doesn't go over 63 degrees ever

 

[FreeStream]

dude heat IS an issue if it's making the cards crash or artifact. Whether your happy with the temps has nothing to do with it

This.

If it is crashing it is crashing.

Take one card out and test them one by one?

 

[Besty]

I have x 2 Hd 7970 Reference cards, trying to over clock them past 1125mhz they become unstable, after reading about it i don't think it's the chips that are failing me i believe it's the over current protection.

I have come to this conclusion as the whole pc power shuts down and restarts, rather than the pc just freezing.

Does anyone know the best way to over clock Crossfire Reference 7970 cards so they are stable.

if you are on air, that is a good clock.

 

[chief barker]

dude heat IS an issue if it's making the cards crash or artifact. Whether your happy with the temps has nothing to do with it

My 7970 at 1174 volts is so almost stable at 1200/1650 it's untrue. i can bench heaven/everything, but every once in a while i get polygon artifacting in BF3 and my card doesn't go over 63 degrees ever

Agree with that, I can get 1125/1575 in bf3 without if artifacting and long graphical spikes. anything above that and it's a no go. 2 7970 windforce.