I read other posts and this is what I learned but not sure if I understand about how a 32 bit OS will use 2gb or 4 gb. I currently run 2 GB of ram and that I have 1.5gb of usable ram for games what ever. If I install 4gb which is the max in win xp pro? will read 3.5gb of usable ram for games and what ever. Since the 500 mb is saved for mmio items. If I upgrade my gpu to a 512 mb card from my 256, my os will reserve around 756 mb of memory and out of the 4 gb , 3.2 will be available? Sorry, Hope you can get what I?m typing, It?s confusing to me. Am I on the right track? Will have to enable anything in my boot.ini?