GTX 570 move to 7870XT

I found a great deal on a used Sapphire 7870 xt.


http://www.sapphiretech.com/presentation/product/?cid=1&gid=3&sgid=1160&pid=1790&lid=1

I already have a heavily overclocked gtx 570 with custom cooler. I'd put it over a 580 at standard clocks anyway.

Anyone with experience in this upgrade path? Also can I expect coil whine with this particular card? I've not experienced it, my current card is quiet as a church mouse.

I really like the performance I get from my current card but I looked and some gpu charts and the XT seems promising and the price is right.

Anyone want to chime in I would appreciate it. 150 bucks for the 7870 xt used is still a pretty good deal. I trust the seller.