Question Computer won't post or turn on. RBG RAM lights up

[nicholasashmore1996]

I just replaced my PSU today as this morning I found my computer crashing when I launched any game. I swapped GPU from computer A (the computer that keeps shutting down) with computer B (Works fine and has no issues). The GPU worked perfectly! I then proceeded to run games on computer A without a GPU and it powered through with some lag which is to be expected.

I went from a 750w modular Supernova power supply 80+ Bronze to 850w modular EVGA Q4 80+ Gold.

Everything is plugged in but when I press the power button nothing happens for a few seconds and then the ram lights up but that is all.
My build:
Nvidia RTX 2070
I7-8700K
G.Skill Trident 3200Mhz 2x 8gb
Gigabyte z390 UD motherboard

 

[rgd1101]

reseat the ram, recheck all cable