I did write a massive post on how I came to get the R9 290X but my work machine BSOD whilst doing so and I dont have time on lunch any more to rewrite it. I shall give a summary.
I purchased the R9 290X 4gb version second hand for £150. It came with an NZXT G10 cooler bracked + a Kraken X31. Tried the card in the sellers PC and it crashed during any slightly intensive task. Even the screensaver killed it. Tried it in my machine and the same issue. Guy offered me a full refund if the card was faulty.
Took the card home to test, card worked fine (lots of fans pointed at it) and had an average temp of 65C Idle which crept up to 75C and 80C whilst attempting to trouble shoot. My next test was to see if the pump was working.