Hey there, Your biggest issue is not the processor. Many PC's are built with 64 bit processors but the thing you really need to look at are the components. A lot of components (video card, sound card, etc.) do not have 64 bit drivers readily available. You can try to find someone to write one for you or decorate one for 64bit but you are looking at the possibility of frequest crashes. If you do have 64 bit drivers for ALL of your hardware components then you should be fine. The hardware manufacturers just don't see a large enough market to produce x64 drivers for all of their hardware. Hope this is useful guidance.
My computer has the 32-bit version of Vista, and I was thinking of upgrading to 64, but I'm not sure if it will work. The Microsoft page on the subject said to check the system variables which do say x86, not x64. However, I have the Intel E8500 processor, which is supposed to be 64-bit. So would the 64-bit version of Vista work or not?

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