Help with overclocking HD6870

[hartacus]

I have a Gigabyte HD6870 I tried to overclock it using ATI Overdrive and MSI Kombustor for testing. When I brought the GPU clock settings to 985MHz and Memory clock settings to 1120MHz id didnt complete the KMARK BENCHMARK Extreme test. SO I lowered the GPU to 980MHz and the Memory to 1115MHz and it passed with a score of 1695 at 39FPS. I then went to run the Windows Experience Index and my comp froze while it said "Running Direct3D Constant Buffer Assessment". Any ideas on why this is freezing during the Windows test but not the MSI one?

 

[Idonno]

Every card OC's differently. You may have to raise the voltage to get your card stable at your OC.

My OC's are as follows:

GPU Clock: 925
Memory Clock: 1100
VDDC: 11.74 (stock Voltage) (Trixx tweak utility doesn't show decimal point)

GPU Clock: 950
Memory Clock: 1125
VDDC: 12.00

GPU Clock: 980
Memory Clock: 1170
VDDC: 12.50

GPU Clock: 1000
Memory Clock: 1190
VDDC: 12.99

Like I said all cards OC differently you may not do as well or you may do better. You just have to monkey around with it until you find settings that work for you.

You will also need a application to OC the voltage. I use Sapphire's tweak utility called Trixx but I don't know if it's voltage control will work for a non-Sapphire card.

There is also msi afterburner as well as an Asus app but again I don't know if their voltage control will work on your card. If they don't work you will have to download another OCing utility.