No post, Slow Bios - PC does not boot after Windows 10 install or post

[TommiSRP]

This is gonna be a complicated one.

SPECS: 
Intel Core i5-13600K
Asus GeForce RTX 3080 TUF Gaming - OC Edition (LHR)
NZXT Kraken X53 RGB
Asus ROG Strix 850W
Gigabyte Z790 GAMING X AX
Samsung 1TB 980
Western Digital 1TB WD_BLACK SN850X

On the first start up the PC started nicely with all peripherials attached and with the monitor connected via display port. BIOS was snappy and worked smoothly with no problems. All components showed up in BIOS and I enabled XMP and proceeded to save the changes and then save & exit. Computer displayed the connected RAM, CPU and the M.2's correctly. 

This is when the problems appeared. Upon starting up the PC it would not notice the monitor via display port. I did try to power on the PC multiple times and the problem would persist. After a while I switched to an HDMI and it would occasionally run for a while. 
Computer would occasionally turn off after being on for a little while. I ended up getting it to BIOS, but BIOS started working extremely slowly. Without changing anything I got the PC to get into the first Windows installation. Installation started and after a while the PC shut down. I thought this was normal and waited for a while, but the PC did not start up again. 

After this the shutting down after booting would continue. On startup the VGA (Graphics card) status LED would light up before shutdown. I re-adjusted the graphics card a little and set the PC on it's back panel. The PC ran for a little while, I ended up being able to set back the default BIOS settings,  after a moment  it did shut down again. I went trough the peripherials too, and none of them would seem to have an effect on the PC shutting down. 

I double checked all the connections and and that the RAM was seated well. 

Because the VGA light had flashed on before I removed the GPU and go the PC to succesfully boot. Note that the BIOS was still slow. The PC did not crash anymore and I was able to boot the PC with the Windows install media in the USB port. I got Windows fully installed and I was able to work around in Windows with seemingly no problems. After the completed Windows install I restarted the PC via the Windows menu. The PC did not restart and started to shut down after each attempt to power on. The problem would persist with no devices connected.
The PC would still occasionally flash the GPU light with no GPU connected. On the attempts when I did get to BIOS it did note that something was connected to the PCI-E port, but did not display the product name. 

I have done these steps of trouble shooting: 
- Checked for faulty peripherials
- Launched with only the monitor 
- Checked both ends of all cables
- Checked the RAM was seated correctly
- Checked the GPU was seated correctly
- Removed the GPU all together

Im completely stumped at this point, I did about 4 hours of trial and error and I have not found a solution. 



 

[Cyberat]

Did you connect D-Port on MB or on GPU ?

Did you disable the Intel UHD ?

If you sit in Bios what are your temps ?

[vertigo220]

Try clearing CMOS. Also test with one stick of RAM, if that doesn't fix it try another stick, then another slot. Sounds like possibly a bad motherboard. Is the BIOS updated on it?

[TommiSRP]

44 minutes ago, vertigo220 said:

Try clearing CMOS. Also test with one stick of RAM, if that doesn't fix it try another stick, then another slot. Sounds like possibly a bad motherboard. Is the BIOS updated on it?

I will attempt these steps today. If I get lucky enough to enter BIOS I will also update the bios. Hell of an expensive board to replace! 

[TommiSRP]

3 hours ago, Cyberat said:

Did you connect D-Port on MB or on GPU ?

Did you disable the Intel UHD ?

If you sit in Bios what are your temps ?

I tried both ports. I have not yet disabled the Intel UHD. In bios CPU reports the temp at around 42C, so nothing overly hot 

[TommiSRP]

UPDATE: 

The source of this problem will remain unsolved. 

I went to a local PC-repair shop after I had done all the troubleshooting steps I felt I was qualified to do.

After a complete teardown in the shop and a updated BIOS all the problems seemed to be solved. It could've been a badly mounted CPU cooler, but this does not really tell the whole story since we got the PC to stay on for a prolonged time a couple times. 
The BIOS update was needed though. The USB2 header in the motherboard which the cooler pump was connected to did not light up the center of the pump as it's supposed to do. The BIOS update also fixed the function of that header, thus lighting it up as it's supposed to be.