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[SOLVED] Dual monitors why no signal in bios and only work when Windows loads?

nunoanjos1

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Apr 18, 2018
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I've connected 2 monitors to the PC, which seem to work fine in Windows 11.

However, when I reboot or start the computer, both monitors show no signal during the BIOS splash screen phase. After that, as soon as Windows starts loading, the HDMI monitor shows image again as normal.

Has anyone had a similar issue? Any fix?

Motherboard: ASUS A320M-K
CPU: AMD Ryzen™ 3 2200G
1st monitor: HDMI
2nd monitor: VGA

When I log on, both monitors show Windows at the same time, so everything seems to work fine in Windows 11.

I already know this motherboard is not 100% compatible with a VGA monitor, for no apparent reason (since it works in Windows), except probably due to corporate greed.

Go figure why the motherboard has a VGA port if it's not completely compatible with VGA monitors. In the past, I already contacted AMD and ASUS asking about this issue, getting mostly ignored or inconclusive confusing answers, some representatives didn't even understand anything about hardware, so that was a waste of time.

During boot, the only difference is, if I unplug the VGA cable (have only the HDMI monitor connected), I see the BIOS splash screen again, that says "ASUS in search of incredible, Press F2 to enter BIOS".

If I connect the VGA cable (have both monitors connected at the same time), none of them gives any signal and no BIOS splash screen is shown, until Windows starts loading.

Since the motherboard only recognizes the HDMI monitor before Windows loads, how come it won't use the HDMI monitor like usual to show the BIOS splash screen if both monitors are connected?

I already tried different BIOS options like enable multi-monitor, HybridGraphics, nothing available there works.
 
Have you checked the BIOS settings that enable the VGA? I'm thinking yes since it works in windows.

They could be no answer if the BIOS is first trying to go to the VGA but can't until windows is loaded.

My 2 screens are 1 HDMI 2nd DP, my splash screen goes to the 2nd monitor with monitor 1 black, if I spam delete and enter BIOS it still goes to monitor 2 with monitor 1 black. After the splash screen ( on 2nd monitor ) it loads windows to monitor 1 with monitor 2 black after I log into windows it displays on both as it should.
 
Have you checked the BIOS settings that enable the VGA? I'm thinking yes since it works in windows.

They could be no answer if the BIOS is first trying to go to the VGA but can't until windows is loaded.

If BIOS is trying to go to VGA as you suggest, why wouldn't it suceed when I have the VGA monitor connected to the VGA port? It works perfectly in Windows, right now I'm typing this reply to you on that VGA monitor.

Which one is the BIOS setting where you enable VGA? I think it's already enabled on my BIOS, I don't have many different options. I only have 3 options.

The guides I googled on how to enable VGA say we only need Multi-Monitor option enabled, mine already is enabled.

I have another option to choose primary display between only 2 choices, IGFx or PCIe. I have IGFx chosen because from what I read, that means integrated graphics, PCIe would be for a dedicated graphics card, I don't have any external graphic cards, my GPU is Vega Graphics 8, integrated in the Ryzen processor.
 
If BIOS is trying to go to VGA as you suggest, why wouldn't it suceed when I have the VGA monitor connected to the VGA port? It works perfectly in Windows, right now I'm typing this reply to you on that VGA monitor.

Which one is the BIOS setting where you enable VGA? I think it's already enabled on my BIOS, I don't have many different options. I only have 3 options.

The guides I googled on how to enable VGA say we only need Multi-Monitor option enabled, mine already is enabled.

I have another option to choose primary display between only 2 choices, IGFx or PCIe. I have IGFx chosen because from what I read, that means integrated graphics, PCIe would be for a dedicated graphics card, I don't have any external graphic cards, my GPU is Vega Graphics 8, integrated in the Ryzen processor.
Yes but like you said that board has VGA problems google it, but it sounds like you already have.
Mine does the same thing but will display on the DP port yours is probably also trying to put it on the 2nd screen but can't display their till windows is loaded.
 
Yes but like you said that board has VGA problems google it, but it sounds like you already have.
Mine does the same thing but will display on the DP port yours is probably also trying to put it on the 2nd screen but can't display their till windows is loaded.

I've already googled it, can't find a definitive answer, that's why I posted here.

I appreciate that you shared your experience. I still think this thread and discussion can be helpful for me and for others, in case someone else reads it and has a better understanding (and resolution) of the issue.

I've found on google posts by other people who have the same motherboard and experienced a similar problem. Sadly, none of those threads has any answers or explanation about why it happens.

I wasn't happy when I contacted ASUS and AMD, they didn't help me at all, just gave the usual ASUS blames AMD and AMD blames ASUS infinite cycle of nonsense.
 
A simple test to do: unplug HDMI monitor, leave only VGA connected, boot. Does it show BIOS screens or stay black until Windows?

I've already done that test, with only VGA monitor connected, stays black (no signal).

With VGA and HDMI monitors both connected, also both of them stay black without a signal.

The only case in which BIOS splash screen shows up is when the HDMI monitor is connected and the VGA one unplugged.

So weird. Right now, in Windows 11, both monitors are working in dual monitor mode.

The BIOS setup even has an option to enable multi-monitor (which I already enabled). This issue doesn't make sense.
 
I've already done that test, with only VGA monitor connected, stays black (no signal).
In that case I would say your issue is not fixable. See, it is the graphic card (or, in your case motherboard) that decides on which monitor it will show BIOS in case of multiple monitors are connected. That setting cannot be changed (or more precisely, I have not yet met a GPU/mobo that would let you change it). So in case of your mobo, it seems will always display BIOS on monitor connected to VGA (unless there is none connected there). And as you already mentioned that, since (for some reason) it is not fully compatible with VGA, it fails to do so.
 
In that case I would say your issue is not fixable. See, it is the graphic card (or, in your case motherboard) that decides on which monitor it will show BIOS in case of multiple monitors are connected. That setting cannot be changed (or more precisely, I have not yet met a GPU/mobo that would let you change it). So in case of your mobo, it seems will always display BIOS on monitor connected to VGA (unless there is none connected there). And as you already mentioned that, since (for some reason) it is not fully compatible with VGA, it fails to do so.

You're right that when HDMI and VGA monitors are connected, the motherboard prioritizes VGA for some reason.

The VGA monitor is working in Windows as we speak. So it boggles my mind why the motherboard fails to connect to that monitor during BIOS boot.

Why does it have a VGA port then if it doesn't work? In terms of hardware, it's ready for VGA, the VGA monitor also works perfectly. A small mystery for man, a big mystery for mankind lol.

The question that theorically it's not fully compatible with VGA as you said, made me suspicious from that start, never convinced me. It sure seems 100% compatible with VGA in Windows 11, where it's working fine.

My guess is either ASUS did something wrong with this motherboard accidentaly that made VGA not work (remember Xbox's red ring of death?) or they made VGA not work on purpose during the BIOS boot, because of corporate greed, trying to phase out VGA and push for the sales of HDMI monitors.

Either way, I'm still curious about this intrincasy. In any physical system, where nothing is exchanged with the outside environment, entropy always increases.
 
My guess is either ASUS did something wrong with this motherboard
No doubt about that, they sure screw up. What I will write here is pure speculation, but this what I think is happening:
Any output needs some code to make it work. It works in Windows - because it does have the necessary code. The BIOS needs the code as well to use VGA output - except unlike the Windows, the amount of memory space BIOS has for code is limited. You might be aware of the fact that some A320 boards have BIOS updates that allow them to use later generations of Zen CPUs - but often at the cost of losing ability to support earlier generations. Why? Because of BIOS limited memory. Same thing could be happening here - due to memory constraints VGA support might have been removed in some BIOS versions. Of course in that case logical move would be to move output priority to HDMI, but maybe they forgot to do so ...
 
What I will write here is pure speculation, but this what I think is happening:

I think you're probably right. Your speculation is welcome, anything to help understand what is happening behind the curtains, inside the machine.

I just found a post by someone who bought exactly the same motherboard, same processor and had the inverse problem: his HDMI port wasn't working, his VGA port was working. Lol made me laugh.

 
UPDATE

Finally, many years later, I solved the issue. After my last reply here, I decided to try updating the BIOS. My hunch paid off.

Something I was always scared to do because people say it's dangerous, can cause the end of the world, or a demon invasion.

My BIOS version was 3803 (2018/01/26), I updated to 5862 (2021/11/05), rebooted and BINGO, it fixed the problem.

I see the BIOS splash screen on the VGA monitor, then when Windows starts to load the image switches to HDMI monitor, after I log on to Windows, I get image on both monitors like before the BIOS update.

If anyone else has the same motherboard and comes across the same problem, I hope this resolution helps.

BIOS version 3803 was supposed to bring compatibility to the new processors back then like Ryzen 3 but it seems ASUS messed up and it didn't work properly with VGA monitors.

Since then, they have released many BIOS updates until now. I still don't know exactly in which update this problem got fixed. There's no information online.

I think ASUS did a poor job, they should have acknowledged their mistake, put online release notes, more information telling people which BIOS update solved this issue.

I found online many users with the same problem, all of them asked the same I did but we never got any answers. Couldn't find anything online or even after contacting ASUS directly.
 
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Glad you found a fix. Looks like my speculation was more or less correct. Seems like Asus did removed VGA support in one of BIOS updates, and bring it back in some later version. I guess I assumed you were on newest version otherwise I should suggest updating it.
 
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Glad you found a fix. Looks like my speculation was more or less correct. Seems like Asus did removed VGA support in one of BIOS updates, and bring it back in some later version. I guess I assumed you were on newest version otherwise I should suggest updating it.

Thanks again for your interest in this problem. Like I said, you were right in your speculation. I was thinking about every possibility because I'm curious, I was intrigued by the issue, I took your ideas into consideration too, before I decided to try updating the BIOS. You talked about BIOS versions, which gave me that hint.

When I bought the PC, the person in the store told me they installed the appropriate BIOS version (3803) for the processor, so I trusted what he said was true. Not so fast. When I got home, I only had a VGA monitor at the time, which didn't work, couldn't use the PC for a while, so I got disappointed.

I never wanted to mess with BIOS because I've read it could be dangerous, I don't know what hardware becomes compatible or incompatible with each version. Also, I've never updated a BIOS before today.

I was worried an update could harm the PC. At the same time, I was so curious and intrigued, I decided to risk it. I thought maybe it will work, maybe it won't, but I won't know until I try. Obviously, I wasn't going to get any help or tips from ASUS.

Today after I read your reply and before I decided to update the BIOS, I contacted ASUS again. I explained the issue to him. He asked me to fill in a form, send by e-mail and his support team would reply back to me in 24 or 48 hours. I also asked him if he knows of any BIOS version that would fix the problem. He replied that he didn't know for sure but told me I could try a BIOS update if I wanted.

I'm disappointed with ASUS. After all these years, I'm sure many other customers like me complained to them about the same issue. They still can't give people the right information when confronted by the issue that affects one of their BIOS updates and one of their motherboards.
 
I'm disappointed with ASUS. After all these years, I'm sure many other customers like me complained to them about the same issue. They still can't give people the right information when confronted by the issue that affects one of their BIOS updates and one of their motherboards.
I guess I can shine a bit of light on that matter too (though that's not a first hand knowledge so treat it with a grain of salt). See, the first level support guys - those that have direct contact with customers, either by phone or mail - are hired based on their ability to talk/write nicely rather then their (in this case) tech skills. So you can often assume the support guy you talk to might actually know less then you! Of course, there is also next level of support which has the people with proper knowledge, so theoretically your question should have been sent there but you know how it is ...
 
I guess I can shine a bit of light on that matter too (though that's not a first hand knowledge so treat it with a grain of salt). See, the first level support guys - those that have direct contact with customers, either by phone or mail - are hired based on their ability to talk/write nicely rather then their (in this case) tech skills. So you can often assume the support guy you talk to might actually know less then you! Of course, there is also next level of support which has the people with proper knowledge, so theoretically your question should have been sent there but you know how it is ...

I know everything you said, I'm aware of how tech support works, I've worked in tech support as well. The problem is this has been a known issue for years, with muliple reports from customers. ASUS even fixed the issue in a certain update (they didn't reveal which one) but ASUS never put the information online, release notes, informing people about what update fixes it and how to fix. A lot of companies do that, upload extensive release notes for updates. If you look now at the page with all their BIOS updates, each one only has 1 or 2 very short vague lines, not informative at all. You can't find on that page any information about the problem I came across with and solved myself without any help from ASUS, when ASUS is the company which had people with that knowledge who couldn't be bothered to share it online for paying customers affected by the issue. That is pure incompetence.
 
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