Hello. I am a *slightly* experienced PC builder struggling with a build and would appreciate some advice.

I am putting together a budget PC for my partner with second hand components. The parts are:

- Asus Prime A520m-k micro atx am4 motherboard

- Ryzen 5500

- Nvidia rtx 3070

- Coolermaster MWE 550w v2 PSU

- 16GB DDR4

- crucial p3 ssd

On (partial) completion of the build (cable management and case closure tbd) it powers on lighting the case fan and initiating the CPU fan, but no display.

I have tried reseating RAM to no effect. I have my own PC (x570/5800x3d/6900XT build) and have so far tested the RAM and GPU in that and can confirm they are working. The motherboard has no post tone or light which I am strongly regretting at this stage. I am ruling out an issue with the second hand SSD as I’d expect to be able to boot to bios with or without it.

I suspect the issue is PSU, motherboard or cpu related, but I really do not want to have to go through testing this in the other chassis, repeatedly repasting CPUs, or pulling the motherboard out of my existing build.

Would be grateful for any advice on where to go next, particularly anything I may have missed so far, before I tear two build PCs apart. I am wondering if I have definitely set the PSU up correctly in the new build and am going to test this next.