After rebooting it, The S3 gets to the boot screen and upon opening an app, promptly shuts down again. Further attempts result in the phone shutting off during the boot animation, and finally now the phone simply shuts down right before the boot animation. (note: it doesn't reboot. It turns itself off).
I thought it might be a problem with Cmod, so I wiped everything and using CWM, installed slimkat. Same problem. so I went and installed stock android using Odin, and now I'm back to stock. STILL same problem.
When I have the phone plugged into a computer, it seems to get further than the boot animation before shutting down (sometimes it gets to the lockscreen before shutting down again).
Any idea what's causing this problem? I have no problems with erratic shutdowns during recovery and download mode.