PC Graphics

[ATX350]

I am getting no video output or POST. The issue seems to be specific to the 6900xt because I am getting video when using an old Nvidia GTX580. This is my 2nd 6900xt after thinking the 1st was DOA. I performed an RMA and just installed the new 6900xt and am having the same issue as before. 

What is your parts list? 

GPU	Radeon 6900xt
CPU	AMD Ryzen 5900x
Motherboard	Asus ROG Strix B550-i
Memory	Crucial Ballistix 3600
Case	SSUPD case with PCIE 3.0 riser
Power Supply	Corsair SF750
Storage	Sabrent 1TB Rocket 4 PLUS NVMe
Other	Sabrent NVMe heatsink  Samsung Q7 32" Monitor

Describe your problem. List any error messages and symptoms. Be descriptive.

No video output and no POST. The Q-LED on the B550 is white indicating no video output:
"VGA LED light is always ON after power on(indicates no Graphics Card or Graphics Card faulty)" 

I am just getting a black screen. The monitor detects a device (not getting "device not detected" error). 

List anything you've done in attempt to diagnose or fix the problem.

• Tried 3 different monitors
• Tried multiple HDMI & Display Port cables
• Tried using multiple HDMI & Display ports on both the GPU and Monitor
• Performed BIOS/Firmware upgrade & downgrade using various versions (including current). 
• Tried different PCIe cables (No daisy chain, 2 separate PCIe power cables) 
• Cleared CMOS several times 
• Installed a different GPU (GeForce GTX580) which works. 

Final thoughts & my next steps: 

I thought for sure the GPU was DOA but after seeing that the 2nd 6900 fails to output video, I am at a loss. Help!  

At this point, the only theories I have are: 

1. The power supply is not outputting the certified amount - I am buying a multimeter and will test it
2. Perhaps the PCIe 3.0 riser isn't beefy enough to support the 6900? I am buying a PCIe 4.0 dual reverse cable to test this 
3. By some small chance, I received 2 DOA 6900s? 
4. Pray

[elstaci · Accepted solution]

When you power up the computer is the HDD/SSD Computer LED light blinking or on steady?

If it is that means it is booting into Windows but without Video Output.

But if the HDD/SSD LED light turns off and doesn't turn on then that seems to indicate it didn't go past POST.

I had a similar issue with my LG 4k Monitor, using both HDMI and DP, and Asus Motherboard using a Nivdia GTX1070 GPU card. I also was getting the VGA Trouble LED Light on all the time when I power up without any Video Output. Unfortunately my HDD/SSD LED  Light was broken so I didn't know if it was booting into Windows or not.

Finally after a couple of days of troubleshooting and having my GPU card and Computer Tower checked at a local computer shop it turned out to be my monitor was not compatible with UEFI Mode on. I only got Video Output when I connected my HDMI 2k TV set.

When I had Video Output to my 2k TV Set I set BIOS to CSM Mode (legacy Mode) and my LG Monitor started working during POST with Video Output again.

Even now with everything working fine, I finally set my BIOS back to strictly UEFI Mode and disabled CSM Mode after upgrading to Windows 11. Now I just get Video Output as soon a Windows starts loading but I still have the White VGA Trouble LED Light on all the time. I read other Asus Motherboard has the same issue with the VGA LED light not going off.

If I need to enter BIOS, I simple disconnect my 4K Monitor and connect my 2k TV to get video output so that I am able to configure BIOS.

Obviously this isn't your case. I suggest you install the GPU card in another computer and see if you get Video Output like I did by going to a local Computer shop.

If it doesn't work in another compatible computer than most likely the issue is with the GPU card.

You can temporarily set BIOS to CSM Mode or Legacy Mode and see if you get video output during POST.

EDIT: According to this PSU website a PC using a RX6900 and Ryzen 9 5900X Processor requires a minimum PSU of 650 Watts. So with your 750 Watt PSU you should have, at least, plenty of power to boot your computer up with your GPU card: https://www.whatpsu.com/psu/cpu/AMD-Ryzen-5900X/gpu/AMD-Radeon-RX-6900-XT

Unless your PSU is defective and not outputting the correct voltages. You can use OCCT to check your PSU Voltages by temporarily using your old Nvidia GPU card to boot into Windows.

I see that you have a Mini Computer case which is why it needs a Riser to connect the GPU card. But according to your Link on your Computer case the Riser is compatible with the rx6000 series GPU cards and PCIe 4.0:

[goodplay]

Are all gtx580 models non uefi vbios (legacy mode) ?

Could be incorrect mobo bios settings and/or ssd format. 

[ATX350]

Thanks for the thorough response. 

I am only using an NVMe drive. This is a new build so I don't have Windows installed yet. 

Hadn't heard about UEFI mode, I'll look into that. 

The case I have comes in two versions, one with PCIe 3 and another with PCIe 4. I have the PCIe 3 version. 

I am waiting on a new DVI to HDMI cable to come in and I'll try using OCCT with the old GPU as suggested and report back. Thanks mate. 

[blafargh]

What brand is the 6900xt?  I had this issue with a Sapphire GPU (as did others) and it was fixed for a few of us with a new power supply.

[ATX350]

This 6900xt is from AMD direct. 

The DVI to HDMI cable came in and I can get into bios using my old GPU. Tried changing between UEFI and legacy but still getting a black screen when switching back to the 6900. 

I also updated my monitors firmware. 

Any other bios settings I should check for? 

[ATX350]

FYI, it was the PCIe riser. I replaced the default riser which came with the Meshalicious case with this and it fixed my boot issues. However, now I am experiencing crashes when in game 5-6 times a day. 

https://www.amazon.com/gp/product/B092JTTLYF/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

[elstaci]

Great that you were able to finally boot into Windows with Video output to you monitor. I guess the Computer case's Riser cable 4.0 wasn't compatible with the RX6900XT. 

As for it crashing during gaming, is this the only time it crashes?  In another words the PC works fine without issues except when playing games.

Try using AMD Settings - Tuning to tune your GPU card to make it more stable during game playing if that is the only issue you are having.

Also check the GPU Temperatures. The Hot Spots of the GPU shouldn't reach 110c which is its maximum operating temperature before it starts to throttle.

If it is overheating during game play try to configure a more aggressive Fan curve using the Tuning feature of Radeon Settings.

Otherwise it probably is the AMD Driver or possibly a power issue with your PSU or defective RX6900XT GPU card.