I wasn't trying to, but I've put several times what the new GPUs are. R9 290x/290 new chips, R9 280x - 7970, R9 270x - Nerfed 7950, R7 260x - 7790. This isn't a solid comparison, but gives you an idea of the performance areas where these ideas are in terms of rebranding. The new naming system makes no sense unless you sit down to understand it which is why anytime I put a new one down I put the rebrand in ( ) for better understanding, or flat out say it. So I'm not trying to be rude, just that the info is there and it seemed like you weren't understanding but rather just repeating. I was under the impression at first that you thought I meant buy the R9 290x, but all I was saying was that card has to hit shelves before the rebrands do, same for reviews and solid pricing. So in short and simple (which I'm pretty positive you understand now) I'm saying wait to see how things fair and what prices are, then determine whether you should get him a cheaper 7970, or an R9 280x. I say this because I have a feeling it will go down the same way the 680/770 thing happened. The 770 was 100 bucks cheaper than the 680 on release and closer to 670 pricing.
I used to love XFX until they went ATI/AMD only. They ditched their double lifetime warranty and always revise PCBs to have less than what they should usually ending up in issues. The double dissipation coolers from current gen back (can't speak of the one pictured yet) have been terrible as well. If you buy AMD, get Saphire or Asus.
Yes fresh install of Windows. It's a pain, but when a machine is that far gone it's almost impossible to make it completely clean. It can appear clean for the time being then you might have trigger events later causing things to pop back up.