Here's the situation: About two weeks ago, I purchased a (non-Apple) external display for use with my 2.16GHz Core 2 Duo 15" MacBook Pro. I put the computer in clamshell mode, and it was running fine for several days. Then one day, while I was editing a photo, it hung for a second, I received the beach ball, and it logged out (of all things!) I've heard of people having an issue where their Mac logs them out after a period of inactivity, but that wasn't the case; I was actually using the computer when it did this. I relogged in, got everything reopened, and work continued for a few more days. Then today, I was editing a Word document, when the same thing happened. I thought heat might be the culprit, so I've opened the laptop's display, but even now with it practically at idle (only things running are FireFox, Word, iTunes and iChat, with none of them really doing anything), the CPU is at 169º and the fans are spinning at 3.5k RPM (2k is normal). Any ideas as to what could be going on? I did a search before posting, but I couldn't find anything like this. Is this a common problem, or am I the only one? Is it an issue with the computer, the monitor, clamshell mode...? Any advice is greatly appreciated. Thanks!