Hello, first time poster and rather new to Tom's Hardware site. I have a couple questions if your community would'nt mind answering for me. I have 2 computers the first is HP a1730n it came with vista 32bit Amd Athalon 64 x2 Dual Core Processor 4600+, I added 4 gigs of ram Kingston 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) , I changed the video card to a 9600gt 512mb. The second computer is Dell Demension E520 Intel pentium D cpu 2.80gigs came with windows vista 32bit I updated the video card with a 8600gt and 4 gigs of Kingston 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400). We mainly use our computers for gaming, I know they are not the ideal rig to use for gaming but its what we have to work with. My question for you is I am thinking about purchasing Windows7. I am not real computer savy but am I correct saying that because we have 4gigs of ram windows vista 32 does not use all the ram, Also am I correct in thinking that only 64bit versions will allow the use of more ram. Are our computers not running as well as they could because we have 32bit version of vista? Now for Windows 7 if I purchase it which version would you suggest I buy that would best suit or computers so that they would perform to the best of their abilities in your opinion? I would be looking to buy the upgrade discs and not the full version because I do not know how to reformat harddrives. Would we be able to upgrade to 64bit windiws7? Thanks for your time.