Windows 7 64 Bit. I was looking a bit and I think the problem is that if the CPU/GPU get at a certain temperature, it decreases the amount of work in order to help them cool down. However, for BTC Guild, it shows it as running but I'm not getting an shares. My mh/s is slow, but I should still be getting some shares.
If you are going to take a crack at mining you really should get and learn to use cgminer.
I'm using pooler's CPU miner and it works well. I was looking at cgminer and am considering using it however it seems more complicated and I am not too knowledgeable about things like this. Maybe if I have an hour or two later on I'll get it but for now at least pooler's CPU miner is doing its job while GPU miner isn't:(.