M17x R4, looking for new graphics card

So recently my 7970M died and I'm looking for a new card to replace it. Mainly I'm looking for something that's relatively cheap (preferably less than $500) and can be obtained from a reliable source. Bonus points for something that's easy to install (plug and play?).

I don't mind the performance of the 7970M and would rather prefer something cheap and reliable over an expensive top of the line card. (Although both would be nice...)

I've done some preliminary research and am considering the...

M17x R4, looking for new graphics card