When you turn it on,
the power LED will light then dim for approx 0.5 sec
then return to full brightness befor the HDD starts to search.
If keyboard has problems,
keyboard caps lock LED will come on then go out.
If your keyboard LED flashes, you have a problem:-
One flash then pause....ROM checksum failure
Two flashes then pause...Ram test failed
Three flashes then pause....Watcdog timer failed
Four flashes then pause....A short exists between row lines on
keyboard
