Well almost. I have a GX620 Dell which I have replaced the power supply thinking that the previous supply had an issue. However the replacement also does not work.
On the motherboard I do see the amber Aux power LED light on. I also see the Network LEDS flashing, when I push the power switch on the fornt on the unit. The Unit still does not power up. Anyone out there with any ideas as to what it may be?
John it can be a bad stick of ram or a bad video card that can hold a mb from posting or the mb itself. try forcing the mb to give you a beep code. remove all the ram and video card and see if you get any cmos beep. if not then it could be the mb or cpu that has failed. most times it the mb that dies. if you have a friend or a local shop you know see if they have a post it card. a post it card will show you if the mb is posting or trying to post with no video.
I can tell you right now troubleshooting that gx620 is not worth the time or money.
If it has bad capacitors you could replace them but it can have bad ones that you cant tell just by looking.After working on literally hundreds of those models its always a bad motherboard of some issue.Since your getting some lights and the fans come on i know its the capacitors.
the gx620 is one of the worst of the dell models to just die without warning.
optiplex gx620,744, and 755 are the one most prone to failure because of capacitors.
find a optiplex 760 or 780 if you want to save some money on a dell.
john there are two issues a pc will do when there no power or post. one is as the person posted above a bad cap or part. the other is a short. most power supplys and mb have dead short protection. most of the time if the dead short is tripped is a video card or a hard drive is pulling to much power at post. it hard to be an internet tech as were not looking at the pc. if it an office pc if you can swap it out and test the other pc (run some burn in tests to see if it the ram or another part causing the issue). if you cant swap the pc out i would swap the ram from another know good unit and see if the ram causing the know good pc to lock up or not post. if it not the ram or the hard drive hanging the mb or pulling to much power then your looking at the mb or cpu issue. if your an in house it guy have your company make a debug kit/recovery kit. ami diag for testing anbd burn in a post it card. to read if the mb is posting and where it hanging. a test video card and know good hard drive with a clean image on it. a drive clone program and a laplink or pc anywhere type program...one that can be booted from dos or a boot usb stick and some usb/ethernet/printer and com1 data cables to do a data move from the old pc to a new one. and or sata/ide to usb cables. on the pc also try it in another outlet and with a new power cord. in buildings it easy for wiring to get lose from age and have a bad ground or floating wire or an overloaded area in a building.