StraitUpFya - Thanks.
All - I got my new PX10000G today and compared it to the dead one. There may be evidence of overheating on the bottom next to the vga connector. I should pull the heat sink to see if I can see more from the top. The heat sink connects at three corners of the board, two sturdy connections at diagonal corners and one with a wimpy dogleg stretching to a third corner. The dogleg on my dead board is bent, it came that way. The heat sink may have not been seated well the whole time, I don't know. The new heat sink is not bent, so I hope this board lasts longer. The new board is installed and everything looks good.