So I come back on Monday, and the computer is froze. I restart, and I'm getting visual artifacts on the screen, and it freezes, usually at the login screen, sometimes it logs in, only to have more video artifacts, and freezes shortly after. I'm pretty sure I fried the video card. I'm assuming that the iMac must have really bad cooling on the video card, and it overheated. Aren't there any safety features to shut down the computer if the hardware is getting dangerously hot?
Diablo miner was one of the oldest miner's out there, so it probably didn't. That was why CGMiner was such a big deal, because it used the ADL libraries to monitor temps and would throttle or shut down the GPU when it reached the preset temps. But CGMiner doesn't support GPU's anymore since they aren't a viable mining device any longer.