I get a kick out of this write up on an HP PS replacement I found on EBay.
"An oversight in installation process could cause short circuit, over
voltage, or over power problem. Any one of these issues could cause the
HIGH POWER power supply to kick into protection mode which temporarily
shuts down the power output and its fan. When this happens, it is best to
correct the installation error in the system and either wait for about 30
minutes for it to be properly restored to the standby state; or you may
disconnect the power cord and connectors, then reconnect everything. This
just like a small UPS in your system to protect your system except the
battery feature."
How can anything that doesn't have a battery feature be like a UPS? :)
T