A customer brought me a Compaq Presario SR1300NX that would not turn on. The PSU tested OK with my tester (not a load tester). Shorting the power switch pins on the Mobo had no effect. I back probed the Mobo connector and shorted pin 14 (PS-ON) to ground; the PSU turned on and the computer booted. Thereafter, the computer would start with the front panel switch. However, when he got home the computer would not turn on once again. He brought it back and, same thing; jumpered the Mobo connector and the computer boots and thereafter boots with the front panel switch. Currently, I am shutting it off, waiting awhile and trying to turn it on again, attempting to reproduce the circumstances that cause it to not turn on. Any idea what is causing this?