Vista - Vista home 32 OEM to Vista home 64???

hi guys firstly let me thank anyone who helps me with my enquiry

i brought a pc a month or so back, not realising the version of vista provided was 32-bit, as the machine is a gaming machine and i will more then likely need to upgrade the ram from the 4gb provided i need to change to 64-bit

i know that there is no upgrade for 32 to 64 bit.

i was wondering if the serial key i was provided for my version of vista (doesnt say if its 32 or 64 bit, it just says "windows vista home premium") would work on a 64-bit version of home premium? as paying for a new serial key just seems like a waste of cash...

the version was installed at manufacturer (ebuyer.com) so im guessing they used an OEM installation DVD.
if my serial key would transfer to the 64-bit version how would i go about purchasing the required DVD?????

thank you for your time

I would assume no because I have Home Premium 64bit and on my disc it specifically says that. The box doesn't but the disc does. Also, 64bit for gaming isn't all it's cracked up to be. No game needs 4gig let alone 3gig. 2gig for gaming is all you need for now. Maybe in the near future you will need some more but as of right now there is no reason to upgrade to the 64bit strictly for gaming purposes. If you were to do 3D modeling or hardcore Photoshopping, then I can see it being practical. I do both of those, hopefully for a career one day, so that's why 64bit and 4gig of ram seemed practical for me. However I do game but I don't see much of a different in FPS compared to people with 32bit.

Windows Vista Alternate Media

Go to this site and order the 64-bit DVD and you will be able to use the same Key. Its about 16 bucks