Precision T3500/T5500/T7500 Workstations Diagnostic Lights and Beep Codes  [IMAGE] If replacing size 2032 battery doesn't work, diagnostics confirms what I was thinking - likely a bad PSU. Can also try:  How to Run a Power Supply Unit Self Test On a Dell Desktop or All-in-One Computer 
Hi there, my computer won’t turn on. The amber light is on, on the motherboard and whenever I press the power button, it blinks along with the 1 and 3. Sometimes it does turn on and I can use it for hours and then I turn it off and go to use it an hour or a day later and it does this blinking thing. Any ideas on what it might be or how I can fix this would be much appreciated. Thanks, Will N.
Dell Precision T3500