Hello All I'm considering an i7 iMac vs. a single proc Mac Pro. I do a lot of long running calculations (physics simulations) that use all available processor cores and last several days. So, I'm a bit concerned about heat buildup in the new 27" iMac. I've read that some think the heat is from the GPU, in this case, it would not be a big problem, as all my calculations only use the main processor, and not the GPU. I know that the 27" iMac is definitely the most bang for the buck performance wise, and the screen is dammed nice, and I have at most about $2400 to spend. So, I'm leaning towards the iMac, but are there any words of caution about heat buildup in long running calculations?