Just thought I'd do a quick update as I am grateful for all the help and suggestions. No matter how hard I tried I couldn't get a stable install. I subsequently went and bought an alternate board in the same price range from Asus. I had a couple of issues with the alternate board whilst installing windows, however on my 2nd installation all went well and it's been up and running now, and has been stable for 36 hours. No matter how hard I try I can't get the 560 ti working on this board either. Don't think it's fried as it briefly put out a display for about 15 seconds on my last attempt at installing windows on the Gigabyte board. Not sure if it's my PSU, although looking at the power consumption of my old 4850 that works flawlessly and that of the 560 ti, there doesn't seem that much difference at idle and only a slight difference under load (not that I've got that far). I've put in a rma for both the mobo and gfx, will be interested as to what the retailer finds when they test. Anyway thanks again!