hi
My computer supports the ram speed PC2-4200 240 pin, DDR2 SDRAM. I am running Window Vista and the OS is 32-bit, Maximum memory allowed is 4GB. Currently, I have 2GB of ram and looking to put in another 1GB or 2GB. But before I do that, I got a simple question to you guys.

Can I buy this ram? (184-Pin DDR SDRAM DDR 400 (PC 3200)) Does my comp support this kind of ram?

Would 240-Pin DDR2 SDRAM DDR2 800 (PC2 6400) work for my computer, and 240-Pin DDR2 SDRAM DDR2 667 (PC2 5300) will work too?

Or do I have to match the exact PC2-4200 ram and can't use the (3200,6400,5300)?

Thx for your time!

try this link it will advise you on what to get .
http://www.crucial.com/