I am shopping for a refeence R9 290. I am thinking reference since I have a Kraken G10 and they are slightly cheaper. I know that NR cards have better cooling and some even have better PCBs with beefier VRMs and such, but i'm seeing dozens of ref. 290's going for under $270 used. Most vendors have a ref. 290 including Asus, GB, XFX, Sapphire, MSI and Powercolor all which I can get used off Amazon for under $275-ish (I have quite the Amazon gift card balance going ATM). One of the sellers' descrptions mentioned that the XFX ref. card was guaranteed to have Hynix RAM. This led me to assume that there is no standard brand of RAM that AMD specifies for their ref. cards and also made me womder what, if any, other differences ref. design AMD GPUs may have. Also, do any of these vendors let you transfer the warranty to a second owner?