Could I be whitelisted please, I'm currently setting up a mining pool for my company using Eligius and I'd like to participate in the development discussion thread.

I managed to get cgminer working on my iMac with a 5670 but the hash rate for LTC is over 100 times slower than BTC.

I'll give you 0.05BTC for it if you still have it

After some tests I've noticed BFGMiner seems to slow down if I'm gaming, it doesn't seem to impact game performance significantly.

If you mentioned which miner you're using it would be easier to tell you what you can do.

With most you have control over the number of gpu threads, I suggest lowering it until you're able to game. Chances are you won't have acceptable gaming OR mining performance, unless you really have a beast of a card.