PC won't turn on

[zxSkips]

I build my PC almost a year ago, and it has worked fine since. But now, it just won't turn on. The lights from the RAM, CPU fans, and graphics card turn on, so I suppose they work fine. None of the red indicators on the motherboard are turning on, so I don't have anything to go on. The HDMI cable is connected to the monitor.

How do I find out what is causing the problem?

[strange13930]

does the monitor turn on?

[Timme]

Lights turning on only means that they receive power.
Do you have a CPU with an integrated GPU? This can rule out the GPU failing.
Worth trying to boot with a single stick of RAM and then another one.

 

[Sawa Takahashi]

It can be a lot of things happening.

This could be a PSU gone bad, a CPU dying or even a defective motherboard. Not counting RAM sticks problems.

I suggest you take time to unplug and replug all cables and make sure they are properly seated.

Next step is to try using only one stick of RAM at a time and try different RAM slots.

You can also try reseating the CPU at this point.

Also, try removing all drives (including the boot drive) in case it is causing issues. You should be able to reach the BIOS screen even without a boot drive.

If nothing worked so far, I think you should test your components one at a time in another computer to determine which one is not playing nice. CPU, RAM, PSU, drives, etc.

If all components are testing good, then it is probably the motherboard.

Hope that helps.