What are the signs of an overheating PCU?
My current case has very poor air flow with no place to put a chassie fan, I don't plan on keeping this case very long. So far I haven't had any problems with heat, but tonight while printing many copies I think it might have overheated. My printer (HP deskjet 6122) has always used a lot of resources, while printing PCU useage is 100% and 0-10% between pages, after about 15 minutes of printing, the computer became unresponsive, and when it was done printing (almost an hour of printing) it remained unresponsive and PCU useage stayed at 100%. The mouse worked, the start menu would show, but I couldn't shut it down, restart, or reset, I ended up killing the power to the PSU.
When I restored power and tried to restart, the power light came on but nothing else happened, not even the PCU, PSU, or video fans. I killed the power again and let it sit for a while (about 10 minutes) and tried again. This time the fans kick in and I get a message about failed overclocking (I have never overclocked it), so I hit f1 for setup then esc and it booted normally. After rebooting I checked the PCU temp and it was about 50C (after sitting for 10 minutes), it normally runs around 38C. Of course, I have no Idea how hot it got after it hads stopped responding.
Is this signs of an overheating PCU? What is too hot for a PCU?
BTW, PCU is 2.5Ghz P4