Quick question, was just wondering if there is a way to cap the hash rate?

Most people are would be like "wtf moar is bettar" but due to personal health issues I need to keep the fans down, so I was wondering if there were flags which could be used to cap the hash rate at a certain level...

ex. I am pulling 700Mhash/s, and would want to cap it at 600Mhash/s so my GPU is not at full load and the fans will be lowered.

I've heard of -s but I dunno what the flag does, i've heard it can help though for things like this?


Thanks all, and happy mining!