Win 7 OEM question

[Rulke]

I know an OEM key will tie a copy of windows down to whatever machine's hardware it is on. How much of that hardware can be chagned before an OEM copy of Win 7 won't work? I assume adding something like more memory or a new video card is ok? I dont want to buy an OEM copy for my new rig, trying to save 60 bucks over retail, only to learn its screwing me over. Thanks.

[Furtwangler]

you're fine.

[guartz]

OEM is tied to motherboard. I think.