If I buy windows vista 64 bit ultimate can I

Use this copy on as many computers as I want or is it just one computer that I can save it to?

OEM has a limit, I don't know how many times though.

Pretty sure OEM is good for one use

Like you can reinstall it on the same pc as many times as you want but im sure its locked to the system you install it on

Im not sure about retail...

Even if you cant, just DL cracks for it, Its not a big deal if you already bought the OS right?

ok, ok, OEM can only be installed once, it wont let you use the same product key 2 times.

retail can be installed as many times, but after 5 you have to call in to say that you need a different product key, and they give it to you for free. also, you are just supposed to only use it on one computer ;)

OEM copy is made for 1 computer. So, if you change your motherboard, CPU or HDD, that is considered new computer.

But but but, all you have to do is find a new key *cough* Berlac or watever Advisor *cough*

All copies of vista are only meant for one computer!

OEM means it can only be installed once and thats it, and it is tied to your motherboard.

Retail means you can transfer the copy as many times as you like, as long as it is only installed and activated on one computer at a time!