i have 768 mb ram..(1 512 mb and 1 256 mb)... 2.4 gig processor... 64 mb video card inno3d gforce4 mx 440/440se.. and 80 gig + 40 gig hard disk... any advice on how i can speed up my pc? for better pc games and office processing... and another question is 512 mb pqi pc 533 compatible with kingston 512 mb pc 400?