What's the difference?

[JeffPell]

I am pricing a new pc build and I decided to go with the WD Raptor 74gb. I was about to order two of them through newegg and I noticed there are two different 74gp raptor drives. One listed at $181 and the other at $236. I am assuming that the more expensive is the one to go with because it's on back order, but I would still like to know what im getting. Anyone know the difference between these two drives?

Thanks

[mrtheshaggy]

Im not sure on performance but one reason is that one is OEM and the other is Retial.