vista 64 bit / 32 bit confusion please urgent help needed.

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hi,
heres my situation. i had a pc from velocity micro- it came with an OEM
version of xp 32 bit home. I bought the upgrade version of windows vista
home premium 32 bit. im at the point now where i realize that my 4gb of
ram is not being used in my 32 bit environment. so i ordered the 64 bit
alternative media disc from microsoft.

my question is how to install this 64 bit disc. will i have activation
problems? do i have to install vista twice? do i really have to
reinstall xp and will that cause problems?

thanks x64 community!


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sniper16
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