I am too noob to do cpu overclocking

last time i tried GPU overclocking and burned my smps as it was from bad brand tho but after that i decided that i won't try overclocking stuff

Burnout 3 takedown running fine with direct x 10 hw rend. but i gets golden alternate band from screen like due to sun light in game. So not playable with annoying gold bands all over screen. I tried to change all setting but it won't go and in sw rend, it won't run nice as in hw rend.
About 5 fps, i saw, i did mistake in burnout revenge as i find it in burnout 3 takedown, i had setting 6x native in burnout revenge thats why i was getting 5 fps. in dragonball z and smackdown 6x native works fine and gives better graphics then ps2 on tv. So i forgot to change that setting while trying revenge on pc. 2x native in burnout 3 takedown giving me 30-40 fps but with golden thick bands in all screen.
Which tekken you guys thinks can run, like if not 4, 5 then 3 might have chance?
PS, i tried mtvu hack version and wow burnout 3 takedown and revenge both is burning everything in 3x native nice in it haha