Athlon 2400/Asus A7N8X deluxe/1GB PC3200/Win XP corp/Koolance liquid cooled system running nice and cool.
I am having spontaneous shutdowns, always (it seems so far) during CD or DVD spin up, such as during software installation etc. The system just turns itself off with no preamble at all. Down.
I, using the Asus Probe software that came with the motherboard, have noticed that the +5V voltage monitor shows it fluctuating whereas the +3V and others are not. I upped the allowable error from 10% to 15% (maximum) and yet the problems persists, though possibly less frequently.
The power supply is and Enermax 430 watt basic whisper variety. Is a vlotage fluctuation sign of a defective power supply and can that fluctuation cause the shut downs I am experiencing?
I should say I have built two of these systems exactly the same and the other system has no problems and the voltage also appears stable as can be. Same power supply in both.
Swap power supplies. Yes, fluctuating voltage is a sign of a bad PS. The voltage variation should be between 1-3% typically. Asus probe is only good for relative reading and should not be taken literally. If you have a multimeter you could measure each pin but I do not recommend this unless you do this kind of work routinely.