Now the last problem I encountered is the fact that cgminer was reporting 600-700kh/s on both my 290 and 290x even though they were only pulling around ~200w combined from the wall and had pretty much no load. I tried a bunch of flags from the litecoin wiki for my cards which did change the kh/s a bit but still wouldn't put a decent load on the cards.
Have you set your intensity high enough? I go for I:18 but that does slow the desktop.
It was on 20 but that seemed to be the general setting suggested, as noted @
https://litecoin.info/Mining_hardware_comparison . Like I said I tried a large majority of those.
I was also using max on the 1gh pool for testing it. Not sure if that makes any difference.