Screen dims slowly then returns.
Prime suspect= monitor. (2yrs old)
Action taken: Latest video driver installed. No change.
Re-seating video card resulted in no display at all along with one long & two short beeps at cold start-up. (meaning= bad bios chip) This is the very first time this machine has done this in four years of flawless operation!
Action taken: Bios flashed with latest available from OEM. Display does stay on long enough to perform some functions; depending on how much rest it gets during OFF time. This condition is two weeks old now and presents the obvious problem of working in the dark. The motherboard battery is four plus years old and also suspect but not yet replaced.
Adding to all this is a questionable main power ON/OFF switch on the front panel; i.e. it was abused (stepped on by an infant) after which it sometimes does not allow the power to remain ON after being depressed momentarily as designed. This will also be replaced when it arrives.
THE REAL QUESTIONS ARE:
1>CAN THE VIDEO CARD PRODUCE THE DIMMING?
2>CAN THE POWER MANAGEMENT BE INVOLVED? (this was turned OFF and is under evaluation).
3>COULD LOW BIOS BATTERY CAUSE ALL OF THE ABOVE?