Question MSI X470 Gaming Plus Max can't enter BIOS but OS loads

[kckndrgn]

Hello all, hoping I can get pointed in the right direction. I have the following hardware but I cannot get the screen to display anything until the OS loads, so I cannot enter the BIOS. According to MSI's site this MB is compatible with the CPU, but I'm thinking I may have received an older board that needs a bios update.
MB: MSI X470 Gaming Plus Max
CPU: Ryzen 9 5900X
PS: EVGA 500w
HDD: 500GB NVME M.2
GPU: MSI Radeon Armor RX580
RAM: PowerX 16GB DDR4 3200

Symptoms: I have the the NVME drive loaded with an Ubuntu OS image and it will load. I do not see any screen output until the OS has loaded, the POST screen is blank. Of the 4 diagnostic LEDS's near the power connector the CPU will light briefly then turn off, nothing else is displayed. If I press the "DEL" key when I see the "NUM LOCK" key light up the system stops, or appears to stop. I can toggle the NUM lock on and off, but there is no display.
On the MSI site the CPU is listed as compatible, but on the MB box it states that is compatible with the 3000 series only.

Does this board need the BIOS updated to work with the 5000 series CPU? This board does not have the button to flash from the USB, so what are the options to flash the BIOS if that is what is needed?


Thanks in advance

 

[Lutfij]

Welcome to the forums, newcomer!

EVGA is the brand of the PSU, while 500W is the advertised wattage. What is the model of the unit? Also, for that build your PSU seems to be below what's necessary for said build. I'd have chosen a 650W reliably built unit to power the entire rig.

As soon as you power up the system, does mashing/tapping the DEL key on your keyboard bring up anything? You should be able to see a sticker on the motherboard either near the 234pin connector or the mid of the board or the top right hand corner, it should state the BIOS version. You could parse images of the stickers on the board(sans the serial number for your motherboard, since we have no need for that).

On a side note, if you're able to boot into the OS GUI, use CPU-Z and see what BIOS version you're on at the time of writing. Here's something equivalent to it on Linux.

 

[Nighthawk117]

The PC would never get to Windows if the CPU wasn't compatible. Do you have multiple monitors? I found this behaviour on my machine recently, I could only get to the bios with one monitor plugged in. It's fixed now but can't remember what I changed.

 

[kckndrgn]

Thanks for info. I'm not running windows, but rather Linux (ubuntu). @Nighthawk117 , I'm only using one monitor and I've tried both HDMI ports on the GPU, I don't have a cable for the other ports.

@Lutfij pressing the DEL key when starting just keeps the system at a blank screen. It appears the keyboard still works as I can toggle the num & caps lock and see the LED light up/turn off.
The only sticker I can see on the board are the model of the board (X470 Gaming Plus Max, next to the PCI_E4 slot), on the ATX power connector (S/N, and "09 CHK6B").

I'll look into the Linux option for getting the BIOS version and report back.

 

[Nighthawk117]

I used to find on my 1060 GPU that the display output on boot would default to a specific port, if you weren't using it you never saw the bios splash screen.

 

[kckndrgn]

So I was able to get the following information running the command 'dmidecode -s bios-version' and 'dmidecode -s bios-release-date'

# dmidecode -s bios-version
H.A0
# dmidecode -s bios-release-date
12/15/2020

From MSI's site it appears support for the 5000 series was enabled at vHB bios release

Is there a way to access the BIOS on this board with this CPU?