It has been a LONG time since I built computers and things have changed. I have a Dell OptiPlex 780 that has started shut shutting down before it's even fully booted the OS (and that takes five to ten minutes). It did this over night and now does it every time I turn it on. Sometimes it will last five minutes, sometimes 20.
There was an inch of dust that I blew out, but that didn't help. The fans are both spinning freely, although not fast. I do not see any bulging or discolored capacitors, either in the power supply or the on the motherboard.
When it shuts down, the LED at the power connector on the motherboard goes out and the power supply loses ALL voltages. The purple (standby?) wire goes from 5v to about 1v. To get the power supply to come back online, I have to unplug it from AC and wait until it discharges. Once I plug it back in, the purple wire is again at 5v and the computer will come back on.
Does anyone know if this is the power supply shutting down or if it's the main board TELLING the power supply to shut down? I would think that if it was the MB< unplugging the power supply from the mainboard should bring the 5v standby line back up? no?
I just don't want to go buy a power supply if that's not the problem. Thanks.
There was an inch of dust that I blew out, but that didn't help. The fans are both spinning freely, although not fast. I do not see any bulging or discolored capacitors, either in the power supply or the on the motherboard.
When it shuts down, the LED at the power connector on the motherboard goes out and the power supply loses ALL voltages. The purple (standby?) wire goes from 5v to about 1v. To get the power supply to come back online, I have to unplug it from AC and wait until it discharges. Once I plug it back in, the purple wire is again at 5v and the computer will come back on.
Does anyone know if this is the power supply shutting down or if it's the main board TELLING the power supply to shut down? I would think that if it was the MB< unplugging the power supply from the mainboard should bring the 5v standby line back up? no?
I just don't want to go buy a power supply if that's not the problem. Thanks.
Facebook
Twitter
Instagram