"If the BIST LED does not turn on or the PSU fan does not spin correctly, the power supply is not delivering power to the computer...." If none of that helps, you may need a new PSU...
I have an Inspiron 3650 that worked fine for years, but now won't power on. When the power cord is plugged in a solid yellow / orange light appears, but nothing I've tried (including a "reset") has worked. I've researched this quite a bit and as best I can tell this is almost always due to either a problem with the motherboard or power supply, and I'm trying to figure out which it's likely to be because a power supply problem is easier and cheaper to fix. To that end, I bought a PC power supply tester and tried plugging in both the 4- and 8-pin connectors from the power supply, but neither one activated the tester. That led me to believe it's a power supply problem, but then I also noticed that the orange light on the power button only comes on when the 8-pin connector is plugged in to the motherboard, which made me suspect maybe it's the not the power supply but the motherboard. Based on the information here or something else I can easily try, can anyone suggest a way to narrow the problem down? I realize that I could just buy a replacement power supply and see if that fixes the problem, but I don't want to waste the money if that's not likely to help, and I don't like returning things I've bought unless they're completely new / unused or defective out of the box. Thanks in advance.
Inspiron 3650 won't power on (solid orange light)