I would try deleting the .bin files in your cgminer directory. Also double-check your overclocking settings in the ATI control panel to make sure some kind of throttling isn't happening. I would also suggest downloading another version of cgminer to another directory and copying your .bat file over.
Thanks mate, I'll give it a go.
I've tried that - new version of cgminer 3.7.2 and still the same

I will try a different PCIe slot on the board.
Edit/ its running like my sole 7950 lol
Very strange. I would try cgminer 3.3.2 or 2.11.3 as well, but I would also change some of your .bat file settings - try worksize 256 instead of 384, make sure it's set to 8192 instead of 8191 (assuming that's a typo), and I would probably remove the temp stuff, but at least increase the temp-target field.