Mid-2010 Mac Pro 5,1 Major Power Issue

I just recently acquired a Mid-2010 Mac Pro 5,1, and it is now having a major issue. When I initially got it (a few hours ago), it worked perfectly fine. However, after letting it sit awhile unattended (while I was in another room flashing an AMD Radeon HD 5870 graphics card I got for it), I come back to find it in the state you see it in these pictures... The Power LED is on, and both CPUA and CPUB Overtemp LEDs are lit red. There is no other activity whatsoever, no fans spinning, hard...

Mid-2010 Mac Pro 5,1 Major Power Issue