For the past few days my MBP has been slow. Ridiculously slow. Beachballing to open safari etc. I have just noticed that as it tries to load things it makes a weird sound. A short burring sounds followed by a long one then a short one. Don't know if that is relevant. Earlier today it froze so i had to do a hard shutdown (hold down the power button) and then it wouldn't boot. I ended up booting it off the snow leopard disc. This problem seemed to start when i started playing wow again but i had it installed for a long time. Could this be heat related?