Solved Question about OEM version.

I know its tied to the motherboard you install it on, but since its cheaper, its what im going for but i was wondering if i was to buy it and put it on my WD Caviar Black 1TB then at a later date if i decide to use an SSD for the OS drive, can it be switch over?

No worries. I've installed OEM on different configurations, one machine at a time & only one running with it installed, & had no problems.