HD4670 overclocking

hello,
I have an 'ATI Radeon HD4670 GDDR3 512MB Gpu 750MHz, 1000Mhz mem. I tried to overclock it to the CCC with the special, but I am getting to the gpu 15Mhz (765Mhz) and the memories of 55mhz (1055Mhz) ... why so little? the maximum set for the gpu is only 778Mhz (+3.8%) and the memories of 1140Mhz (+14%). ke up the gpu is almost untouchable and memories can be occare even 15%, say that running a risk by taking 1140Mhz? dissy does not cover the memories, that risk is too surriscaldino (in full temp. max 82 ° C)? otterrei benefits occando the card with my current cpu (config in sig)? RivaTuner with the memories of up to 1500Mhz (1250Mhz me to put on the alert) and the gpu up to 1125Mhz (940Mhz to put me on alert)

hi,
if you are willing to overclock more you replace the board of the GPU heatsink.

Hello, leave it to stay as it is, overclock the video card to gain 3 / 8 fps for me it makes no sense unless the gain in performance is very high, eg. COD4 is a default of 70fps, you overclock it 78fps changing, but if it goes from 70 to 100 and a why. I hope that I explained well.

hi,
you can improve the performance of at least 20% without raising the temperature above 90c ° stress is acceptable (performance, not the overclocking: it is not proportional representation come into play because other factors such as RAM etc ...)