Question My RX 6800 sometimes won't start with monitors plugged in ?

[Koirapingviini]

I noticed this thing where on some boots, my computer wouldn't get past the bios screen. Instead of getting into windows, the monitors would go black and say no signal. My solution to this was to power off the computer with the power button and try again couple times and it worked almost every time on the third try.
One time, when the monitors went black and I restarted my monitor, I got into windows, but the computer was using the basic display drivers with the resolution locked to something very low and after a minute the whole computer froze so I had to power it off.

After that I realized that, if I start the computer without any monitors plugged in and plug them later, the computer boots normally.

Also, after switching out the rx 6800 for a gtx 1080, the problem stopped happening.
I've used DDU to reinstall gpu drivers and have formated my drives while reinstalling windows, but it didn't help.

I've tried using one and two monitors, with display port and HDMI cables, without any luck.
I've reset the BIOS into factory settings, but haven't reset the CMOS.
I've also tried older and newer BIOS firmware.

Could the problem be software related or is the card the problem?

 

[Lutfij]

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.

One time, when the monitors went black and I restarted my monitor, I got into windows, but the computer was using the basic display drivers with the resolution locked to something very low and after a minute the whole computer froze so I had to power it off.
Seems to me like your OS is corrupt or your drive is faulty/failing. You mention reinstalling your OS, did you recreate your bootable USB installer for said OS to rule out a corrupt installer?

Also, after switching out the rx 6800 for a gtx 1080, the problem stopped happening.
Could be your used GPU is the culprit.

I've also tried older and newer BIOS firmware.
Please don't downgrade BIOS versions as that may lead to a bricked board.

You might want to source(borrow, not buy) a reliably built PSU with more power than your entire system needs to see if the issue is resolved.

 

[Koirapingviini]

When posting a thread of troubleshooting nature, it's customary to include your full system's specs. Please list the specs to your build like so:
CPU:
CPU cooler:
Motherboard:
Ram:
SSD/HDD:
GPU:
PSU:
Chassis:
OS:
Monitor:
include the age of the PSU apart from it's make and model. BIOS version for your motherboard at this moment of time.

One time, when the monitors went black and I restarted my monitor, I got into windows, but the computer was using the basic display drivers with the resolution locked to something very low and after a minute the whole computer froze so I had to power it off.
Seems to me like your OS is corrupt or your drive is faulty/failing. You mention reinstalling your OS, did you recreate your bootable USB installer for said OS to rule out a corrupt installer?

Also, after switching out the rx 6800 for a gtx 1080, the problem stopped happening.
Could be your used GPU is the culprit.

I've also tried older and newer BIOS firmware.
Please don't downgrade BIOS versions as that may lead to a bricked board.

You might want to source(borrow, not buy) a reliably built PSU with more power than your entire system needs to see if the issue is resolved.

Thanks for the reply!

CPU: 5800x
CPU cooler: Coolermaster Hyper 212
Motherboard: Gigabyte X570 I Aorus Pro Wifi
Ram: 2x16gb Hyperx ddr4
SSD: 970 Samsung
GPU: Radeon RX 6800
PSU: Corsair RM750x
Chassis: NZXT H200i mini-itx
OS: Windows 11
Monitor: Acer Predator XB271HU A

PSU is about 4 years old
BIOS is F32, but tried F36

I downloaded the Windows installer on to a USB stick.

Edit
I should also add that the temps stay under 85 degrees during an hour long Furmark test.

 

[Kreploon9]

Furmark is a rubbish tool, since cards throttle anyway.

Just test it under games that are harder to run for your GPU and uncap the FPS.