Question : Problem: Computer just shuts off and power LED goes amber on tower

I have a Dell 4700.   When I start it up sometimes it will bootup, sometimes it won't.  If it does boot all the way or part of the way it will eventually shutdown on it's own without warning.    When it does this it just goes black and the power led on the tower goes amber.   It will not reboot usually for a while.   The tower power light stays amber.   Then it will evcentually reboot a;ll or part of the way again.  It can stay booted and running for days, other times as I stated it will not even boot all the way before this happens.   I put in  a new power supply but that did not do the trick.   Any suggestions?

Answer : Problem: Computer just shuts off and power LED goes amber on tower

If all the LEDs are green, then nothing is wrong. I think you have issue with power supply that is thing the LED diagnostic wont tell. Check the fan inside the PSU and monitor it works for a while. If it goes idle sometime that is problem.

If you call Dell support, they would tell you to do following steps (one of them is LED diagnostic). If said leds are green they will tell you nothing is wrong.