Compaq Presario CQ56-115DX

I tried to read the thread about the NVIDIA settlement on the CQ56-115DX, but it's really long and filled with many useless comments (a lot of chatting that I don't need, if only someone would post the important pages) Anyhow, my CQ56--115DX is still stock, and it's running at 55 idle 70+ full CPU. What I can I do to bring the temps back to new condition. I've regreased the processor with antec nanodiamond7, but still need to get a new pad for the GPU. I'm unsure whether I should just grease the GPU, since I know the grease above seems to become more viscous as it cures.How often does the fan need to be replaced?

I'm asking this because in a couple of months I would like to buy a new processor and RAM. I've read the manual, but it doesn't seem to be specific on how much memory this laptop can take. I remember reading something a long time ago about the V140 processor only able to handle 4GB (or maybe that was the max speed of the RAM?), but if one upgrades the processor, it can take up to 8GB. And when it comes to processors the NVIDIA settlement thread mentions that S1G4 processors work. Will any S1G4 processors with 25W TDP work? The manual names a few processors, but apparently there's more, since the users on the NVIDIA settlement thread seem to have shown others to work. I would really appreciate an HP representative's knowledge or someone who's dealt with this before, because in Brazil you can't afford to make a mistake, as Brazilian Customs charges ridiculous tariffs on incoming goods!