Windows Update killed BIOS display? (Asus X570-PLUS, 5900x, 3080)

omatsei · April 14, 2021

An interesting thing happened last night. At around 1:30am, my PC with an AMD 5900x and Gigabyte 3080 got a cumulative Windows update (KB5001330) and restarted. When it did, it stopped at the BIOS and the display turned off. I tried booting it a few times, but couldn't get anything on the display at all.

I took out the 3080, and put in an old 970, and it booted. Except it paused on the BIOS screen saying that it had to enable CSM for Windows to start (or something similar). I had disabled CSM last week to enable Resizable BAR, which has been working great. I let it disabled, and watched Windows boot and finish installing the update. When it was done, I rebooted a couple times to make sure it kept working. It's weird that I had to take out the 3080 and put in the 970 to get a Windows update to work, but whatever... it's par for the course for this computer, from what I've dealt with over the past month or so.

I shut down, swapped the 970 out and put the 3080 back in, and it booted to Windows. I rebooted a couple times, to make sure it worked, no problem. However, I can't see the BIOS. Whenever I hit F2 or Del while booting, the BIOS apparently shows up, because Windows doesn't, and the green Q-LED on the motherboard for BOOT stays lit, but I can't see anything. I tried the HDMI port and DP port on the GPU, but nothing appears. If I do NOT hit F2 or Del, it boots fine, but I can't disable CSM (and therefore, can't enable Resizable BAR).

At this point, I'm running without Resizable BAR, but I'd like to get it re-enabled.

Am I crazy to assume that the motherboard isn't fully initializing the GPU before I enter the BIOS? How would I fix that? Has anyone ever seen something like this?

Kimipollo · May 1, 2021

I am in the same situation, I had a resizable bar activated and working and it was updating windows with the update KB5001330 and as soon as I turn on the computer with csm deactivated I lose the video signal in the bios. At the moment I have csm activated so as not to lose the signal and be able to enter windows on my LG C9. I will wait for the May update and if I see that I do not solve the problem I will finish by formatting and we will see what happens.