[Teh Solution]

If I was to buy a Windows OS say from newegg how many installs do I get? For example if I have 3 computers, can I install it on all three,two, or just one. I have Windows 7 RC now. I'd like to buy it, but if I can only install it on one computer, then it may not be worth the cost. Also if I need to do a re-install how does that work, any restrictions on this?

[Hefemeister]

You can only have one product key installed on one computer at a time. The amount of times you can reinstall or uninstall it on one and put it on another varies upon if it is a retail or OEM copy.

Here is the info for the differences:
Differences between OEM and Retail

[Mak213]

As Hefe said, 1 serial = 1 PC. You can reinstall on that PC as many times as you want. As long as you dont change the mobo. Microsoft considers that a new PC and you would have to buy another copy.

Look into the family pack. 3 serials for about $150. Can cover all your PC's then.

[Teh Solution]

Awesome, Thanks guys