Overclocking issues with ati radeon hd 6770

[irvas019]

Hello guys
For few months I have ATI Radeon HD 6770 MSI 1gb GDDR5 and since I'm not able to upgrade, I tried to overclock to gain some extra fps.
Max possible settings in CCC are 960 for core and 1445 for memory clock, so max core clock that I set is 900mhz and memory 1160, because I was afraid to raise more. After that my screen started to "jump" sometimes so I raised power from 1125mV (standard) to 1188mV (I read somewhere that solution for unstable overclocking is when gpu don't have enough power and raising over 1187mV is risky).
Temp in full load is 67-70C, fps +10 and game itself smother. But problem with "jumping" screen is still there and sometimes I lose screen and need to restart pc. After restart, settings in CCC are back on defauIt.
I know that I'm doing something wrong and didn't find concrete answer so if someone know stable overclocking settings or any kind of solution I would be grateful.
My specifications if needed at all:
Cpu - i5 2400 3.1Ghz
Ram - 8gb ddr3
Mobo - asus p8h61-m lx3 r2.0
Psu - 500w
Apologies for bad english, big and messy content I hope you can understand me.

 

[King_V]

The original speeds are 800 for core clock and 1000 for memory.

You have made enormous jumps right out of the gate! I am surprised that it works at all!

You should take a much slower, incremental approach. Try maybe 20Mhz at a time, and see how stable it is.

 

[irvas019]

Yes 800 for core but 1100 for memory. I raised for 20mhz both of them, then test custom clocks and if passes I raised for 20mhz more, not immediately from 800mhz to 900mhz ie. from 1100mhz to 1160mhz.

 

[King_V]

Well, obviously, it's either unhappy with the 900 core clock, or unhappy with the 1160 memory clock.

I would strongly recommend backing down those overclocks.

 

[irvas019]

Setting are now on default, until I find solution if there is any.

 

[Traditore]

It usually can't overclock and be stable above 850 core. That is just not the tier of GPU that can handle OC. No profit to OC this card whatsoever.

 

[irvas019]

Oh ok, thanks man. That is all what i need to know, is it possible or not, since there are no concrete answers. I will leave it to default then.