well for one if you have two hard drives, one an EIDE
hard drive and one a SATA Hard drive make the SATA drive your boot drive and the Eide drive your data drive, secondly you can also shop on line for computer parts the best sites are newegg.com
axiontech.com performancepcs.com and directron.com
all of these stores have excellent service and great reviews at resellerratings.com
and to anwser the main question about vista any pc that runs xp (smoothly) meaning quickly and not strained or underpowered will run vista . the biggest gain for most would probably be the addittion of some x tra memory
and if building your own very important to get a good motherboard( MOST) important because your processor will either be amd or intel both great processors with good support, but if you get a cheap off brand motherboard you may have problembs with your bios
things like not being compatible with certain brands of memory, and all sort of troubles having a good mobo from a top manufacturer with a good bios and good bios updating to ensure compatibly now and down the road is crucial

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