Question Motherboard not doing anything

[Merilsion]

I am a fairly experienced PC builder, but I just can't seem to get this PC to work.
PC Specs:
CPU: Ryzen 7 5800XT
MOBO: MSI B550 Pro-VDH
RAM: G.Skill Ripjaws 32GB (4 x 8 GB)
Storage: Western Digital Black SN770 2TB M.2
GPU: ASUS ROG STRIX GAMING OC RTX 3060 12GB
Case: Lian Li A3-mATX
PSU: Lian LI SP 750

Essentially, I put everything together and when I pressed the power button nothing happened. No fans or anything. The MOBO is sending power because when I unplug the PSU cable from the GPU, a red indicator light comes on.

I have tried the following:

1. Changed PSU to both an EVGA and SAMA, same issue.
2. Changed CPU to a Ryzen 5 3600, same issue.
3. Changed case (I thought it might be an issue with the power button, same issue.
4. Changed MOBO to an ASUS TUF Gaming A520M-PLUS (the RGB on the board came one), same issue.
5. Tried running with 1 stick of RAM, same issue.
6. Tried using different outlets around my place, same issue.
7. Tested PSU with paperclip test, both passed.
8. Tried to manually bridge power, same issue.
9. Took out CMOS battery for 5 minutes, same issue
10. Tried many of these steps outside of the case on the anti-static bag, same issue.

I saw something about the MOBO being shorted somewhere, but I am unsure. The screws the case came with don't look like regular MOBO screws so I am going to try changing the standoffs and screws to see if that helps. Would really appreciate some input. Would really appreciate some thoughts cause I have been at this for like 4 days now. Ideally I would not need to buy any more parts.

 

[Lutfij]

Welcome to the forums, newcomer!

Essentially, I put everything together and when I pressed the power button nothing happened. No fans or anything. The MOBO is sending power because when I unplug the PSU cable from the GPU, a red indicator light comes on.
Did you breadboard the system to verify nothing came dead on arrival? Try with 2 sticks of ram instead of 4, populating slots A2 and B2 on the board.

Changed PSU to both an EVGA and SAMA, same issue.
Please elaborate on the make and models of both PSU's used(and their age if they've been in service for a while).

Tested PSU with paperclip test, both passed.
This test is flawed, it doesn't tell you how much power the system can effectively output, except showing you that the fan in the PSU spins.

I saw something about the MOBO being shorted somewhere, but I am unsure. The screws the case came with don't look like regular MOBO screws so I am going to try changing the standoffs and screws to see if that helps
You stated being a fairly experienced builder, for the sake of relevance, include images of the screws you're working with in case you're confused and we're on the same page.

Your motherboard has a Flash BIOS button on the back, use this guide;

View: https://www.youtube.com/watch?v=MYL88wjbmbI

to reflash the BIOS with the latest version

 

[Merilsion]

Welcome to the forums, newcomer!

Essentially, I put everything together and when I pressed the power button nothing happened. No fans or anything. The MOBO is sending power because when I unplug the PSU cable from the GPU, a red indicator light comes on.
Did you breadboard the system to verify nothing came dead on arrival? Try with 2 sticks of ram instead of 4, populating slots A2 and B2 on the board.

Changed PSU to both an EVGA and SAMA, same issue.
Please elaborate on the make and models of both PSU's used(and their age if they've been in service for a while).

Tested PSU with paperclip test, both passed.
This test is flawed, it doesn't tell you how much power the system can effectively output, except showing you that the fan in the PSU spins.

I saw something about the MOBO being shorted somewhere, but I am unsure. The screws the case came with don't look like regular MOBO screws so I am going to try changing the standoffs and screws to see if that helps
You stated being a fairly experienced builder, for the sake of relevance, include images of the screws you're working with in case you're confused and we're on the same page.

Your motherboard has a Flash BIOS button on the back, use this guide;

View: https://www.youtube.com/watch?v=MYL88wjbmbI

to reflash the BIOS with the latest version

I have been trying all of these on a breadboarded motherboard. I have tried both 2 sticks of RAM and 1 stick.

All parts all new except for the GPU and the Ryzen 5 3600 I used in place of the CPU. The EVGA is a EVGA 650 BP and the SAMA is a SMA 750W GT 750.

Below is an image of the type of screws I am using.

I will try to flash BIOS and report back

 

[Merilsion]

Welcome to the forums, newcomer!

Essentially, I put everything together and when I pressed the power button nothing happened. No fans or anything. The MOBO is sending power because when I unplug the PSU cable from the GPU, a red indicator light comes on.
Did you breadboard the system to verify nothing came dead on arrival? Try with 2 sticks of ram instead of 4, populating slots A2 and B2 on the board.

Changed PSU to both an EVGA and SAMA, same issue.
Please elaborate on the make and models of both PSU's used(and their age if they've been in service for a while).

Tested PSU with paperclip test, both passed.
This test is flawed, it doesn't tell you how much power the system can effectively output, except showing you that the fan in the PSU spins.

I saw something about the MOBO being shorted somewhere, but I am unsure. The screws the case came with don't look like regular MOBO screws so I am going to try changing the standoffs and screws to see if that helps
You stated being a fairly experienced builder, for the sake of relevance, include images of the screws you're working with in case you're confused and we're on the same page.

Your motherboard has a Flash BIOS button on the back, use this guide;

View: https://www.youtube.com/watch?v=MYL88wjbmbI

to reflash the BIOS with the latest version

I flashed with the latest BIOS and the same issue still persists.