Me overclocking 7970

[grandpatzer]

So this is my log for overclocking my 7970:

MSI Kombustor:

1125/1375:
FPS: min 139, max=144, avg=141
VDDC starts from 1.057v but goes to 1.051v
during the run in kombustor.


925/1375:
FPS: min 116, max=119, avg= 118
Gpu-z VDDC=1.057v

So just overclocking core kombustor fps avg increase:

141/118= 19.5% more fps over stock
overclock= 21.6% over stock on core.

Question: Kind of strange that overclocking requires less volts?
The performance increase seems to be good, just overclocking the core by 21% I get 19% more FPS in MSI Kombustor.

 

[AdamK47]

I tried MSI Kombustor on my Tri-Fire 7970 setup and the most it could do on each GPU was 34% utilization. Didn't even get them over 75°C. I've had better luck looping Unigine demos.

 

[RavenSEAL]

It's a trap!

 

[Madcatatlas]

Another 7970 where all you need to do is just slide the OC all the way to the right?...


it will be interesting to see what 7970 Anandtech benches against the probably very late 780.

 

[The Sauce]

Volts are dropping due to increased draw - vDroop.

 

[skipsneeky2]

While nearly a dead thread,i have been looking for the best overclock at stock voltage or near it for the best thermal to performance ratio and have come up with this perhaps for the masses....

gpu-z 6.0 stock voltage vddc readings with furmark running with card at...

1125/1575=1.078-1.084
1150/1575=1.064-1.076

 

[MrK6]

While nearly a dead thread,i have been looking for the best overclock at stock voltage or near it for the best thermal to performance ratio and have come up with this perhaps for the masses....

gpu-z 6.0 stock voltage vddc readings with furmark running with card at...

1125/1575=1.078-1.084
1150/1575=1.064-1.076

Yep, CCC limits (1125/1575) is usually the way to go. It's easy and on a lot of 7970's you don't have to touch the voltage. The 7970's will give a tremendous performance boost for very little extra power if you just crank the clocks to max on stock voltage, for instance, read the chart at the bottom: https://docs.google.com/spreadsheet...FlmUGVQMUZReHI0bFg4czR1Z3AwdXc&hl=en_US#gid=7 . Running a stock voltage overclock gives ~60-70% the performance of a maximum overclock with very little extra power consumed (10W in that case).