Diagnosing a formerly working computer.

Jun 24, 2018
I am unsure if this is the proper location for this thread, but here it is anyway.
I have a desktop computer that I built 4 years ago. It has been moved frequently, as I go back and forth to college ~2 times a year.
It was a budget computer that I upgraded slowly.
When I graduated and moved out of college for the last time, my computer will no longer boot. By this I mean I do not get any display, although fans spin and LED's light.
I tried multiple monitors, graphics cards, and means of output. There is no integrated graphics.
When I turn the computer on, connected keyboards have the caps lock light flash and stay off, and does not function after. Similarly, the CD drive indicator at the front flashes rhythmically and the disk indicator light does not do anything. There are no beeps.

I have narrowed the problem down to either the PSU or the motherboard, but after reading it seems far more likely to be the PSU.
Are there any ways for me to verify that this is the issue without having to go buy new parts and test them?

Motherboard is ASRock - Z77 Extreme4 ATX LGA1155 Motherboard
PSU is Antec - Basiq 430W 80+ Certified ATX Power Supply

Thank you for your time.
Some simple things for you to try.
With the PC off, press the Clear CMOS button on the back panel of your motherboard for 30 seconds.
Try booting without any drives connected.
Try booting with the video card in the 2nd x16 slot.
Double check all the RAM sticks are seated properly in their slots.
Try booting with just 1 stick of RAM installed.

If none of those help you should take the motherboard out of the case and see if it will boot properly outside the case.