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Question "No Signal" displaying on monitor

Nov 26, 2018
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Hi all,

So let me start by linking my build: https://pcpartpicker.com/user/HopsandHerbs/saved/#view=qsz299. *Also, I am sorry for the long read, but I get a strong feeling you smart folks have an answer for my issue.

I've been troubleshooting this for over a week, and here's how it started; Recently upgraded my GPU to an RTX 2070. Installed fine and everything worked great for about a week and a half. Was experiencing intermittent "9C" codes on the Motherboard before that, so when I installed the new GPU I took the opportunity to replace the CMOS battery and boom 9C was fixed. Next came a cheap RBG kit (w/ a wireless RF remote) in the mail from Airgoo. It's 2 LED strips with an LED controller that's powered via SATA. Installed that and no problems. PC worked as normal for about a week.

Went to turn on PC one day and Motherboard would turn on and display code "Ab" (or possibly it was A6 but I don't think so), but the monitor just said "no signal". Here's where it gets weird; Removed GPU, plugged displayport into MOBO, went into BIOS and made sure I had the right SSD chosen for boot priority (I did, and I unplugged the other drive to rule it out). The first few attempts resulted in blue Windows logo displaying, and twice I was able to get my Windows log-in screen to display for a few seconds, but after that the monitor goes back to "No Signal". Despite this, MOBO now displays either "04", "AO", or "AE" which all indicate everything is fine? Given the headway I thought I was making, and the "ok" codes I was getting from the MOBO, I re-installed the GPU and now the PC turns on, MOBO displays "AO" or "04", but now with the GPU in all I get on my monitor is "No signal", now without any Windows logo at the beginning.

I've tried an HDMI cable. I've tried setting default display adapter to "IGFX" in the BIOS (which seems to be the integrated graphics, since without the GPU that seemed to be what I had the most luck with). With the GPU installed I've also tried it with default display adapter set to PCIe 1 in BIOS - with Integrated Graphics disabled. I've unplugged SATA cables and tried different ports. I've rebooted with one RAM stick at a time. I've unplugged everything in the PSU and plugged back in. I've plugged my laptop into the monitor and the monitor works fine.

At the end of the day with the GPU in I can't get anything other than "No Signal" from the monitor. That applies to both having the display port plugged into the MOBO, and then the GPU separately. Been troubleshooting this for a week and am at a total loss. If there is anyone who can help me please let me know what you think, because frankly money is too tight at the moment for me to bring this to a shop.

*I'm not super knowledgeable on this, but is it possible my BIOS regressed to an older version and it's having trouble communicating with anything? I can't even get the computer to boot in safe mode, and if that's the case I have no clue how I would attempt to try updating the BIOS. Anyway, sorry for the long post. If anyone can help me I would be so grateful.

- Brendan
 
To confirm: you can get to the BIOS screen consistently with either and it's just the windows load that fails, or just the igfx work?

Simplify things and pull the 2070 out of the system. Need to get windows booting, then can troubleshoot that.

Disconnect everything not needed to get to windows. Extra drives, the lighting kit, etc.

You may need a CMOS reset to get to igfx if you disabled that.

Disable fast boot options in the BIOS

If you can get into BIOS with the IGFX and windows is failing by booting, then going to blackscreen, can you get into windows by forcing safe mode?
You can do this by interrupting and failing out the boot process 3 times in a row, then the 4th boot should take you to the recovery console, or using your installation media to get to a command prompt and setting the boot policy to safemode.

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The following came from : https://www.digitalcitizen.life/4-ways-boot-safe-mode-windows-10.
all credit to the original author for summing it up simply as below.
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Interrupt the normal boot process of Windows 10 three times in a row
If Windows 10 fails to boot normally three times over, the fourth time it enters by default in an Automatic Repair mode. Using this mode, you can boot into Safe Mode. To trigger the Automatic Repair mode, you must interrupt the normal boot process three consecutive times: use the Reset or the Power button on your Windows 10 PC to stop it during boot, before it finishes loading Windows 10. If you use the Power button, you might have to keep it pressed for at least 4 seconds to force the power off. When Windows 10 enters the Automatic Repair mode, the first thing you see is a screen that tells you that the operating system is "Preparing Automatic Repair."

Preparing Automatic Windows 10 Repair
Then, you may be asked to choose an account to continue. Choose an account that has administrator permissions, and type its password. If you are not asked this information, skip to the next step.


Choosing an account to log in
Wait for Windows 10 to try to make an automatic diagnosis of your PC.

Diagnosing your Windows 10 PC
On the "Automatic Repair" screen, press the "Advanced options" button.

Accessing the advanced troubleshooting options
Then, choose Troubleshoot.


Troubleshooting Windows 10
From here on, the steps you have to take are the same as those we have shown in the first method from this guide. Follow the path "Advanced options -> Startup Settings -> Restart." Then, press the 4 or the F4 key on your keyboard boot into minimal Safe Mode, press 5 or F5 to boot into "Safe Mode with Networking," or press 6 or F6 to go into "Safe Mode with Command Prompt."

Use a Windows 10 installation drive and the Command Prompt
If you have a Windows 10 setup DVD or USB memory stick lying around, you can use it to boot your broken PC with Windows 10 into Safe Mode. Use it to boot your broken Windows 10 PC from it and wait for the installation environment to load. Choose the language and keyboard layout you prefer and click or tap Next.

The Windows 10 Setup
Click or tap on the link that says "Repair your computer" on the bottom left corner of the screen.

Repairing your Windows 10 computer
When asked what option you prefer, choose Troubleshoot.

Troubleshooting Windows 10
On the "Advanced options" screen, click or tap "Command Prompt (Use the Command Prompt for advanced troubleshooting)."

Starting the Command Prompt
Inside the Command Prompt window, type the command: bcdedit /set {default} safeboot minimal. Press Enter on your keyboard and, after a moment, it tells you that "The operation completed successfully."

Activating Safe Mode from the Command Prompt
Close the Command Prompt and choose to Continue on the next screen.

Continuing to Windows 10
After your PC reboots, Windows 10 starts into Safe Mode. Log in with a user account that has administrator permissions, and perform the changes you want.

IMPORTANT: The problem with this method is that it tells Windows 10 to enter Safe Mode automatically, every time you start it until you tell it not to. To disable this setting, and get Windows 10 to boot normally again, run the same procedure one more time and type the command: bcdedit /deletevalue {default} safeboot.
 
Thank you guys for your thoughtful responses. I think ultimately getting the PC to boot to safe mode using the W10 installation disc is what I'll try since I've been unable to get it to boot in safe mode any other way.

Cherry to answer your question; I am only able to get to bios at all without the GPU in, so yes I will definitely remove that for now. Without the GPU in I can consistently get to bios, and that is the only time I can get the monitor to stay on indefinitely, where otherwise when I press the power button I get the Windows 10 logo for a few seconds, the swirling dots below that, and then I watch the monitor "switch off" to the message reading "DisplayPort No Signal". Did I mention I replaced/reset the CMOS recently? Just curious if this would have messed with the bios.. I'm noob-ish.

I assume I'll end up disassembling the whole tower this coming weekend, but obviously any other advice/things to try would be greatly appreciated. Also does anybody know if it's a good sign my main SSD is ok if I was able to actually see my login screen for a second on one occasion? Worried about my components of course - because I don't know things.

So yeah, will try the safe mode/install disc method next to try and get to a point where I can update the bios. Will report back.
 
Thanks to everyone, and Cin19 you were right on the money

Took a week of troubleshooting but I finally noticed the BIOS version on my MOBO had regressed to the version it shipped with. I downloaded BIOS update files from manufacturers website on a separate computer to a thumb drive, then updated my BIOS from there. Finally got the PC to boot - even with the GPU in. The only persisting problem is things are not running properly and only HDMI will work (no DisplayPort signal still). Tonight I'm going to manually install the GPU drivers even though Nvidia says I have the most current driver. I've heard DisplayPort issues can be solved by updating vBIOS in GPU. When briefly testing Subnautica and Battlefield 1 last night it was very jittery, and not just low refresh due to the HDMI. Hopefully the steps I'm planning on taking tonight will get everything back to that sweet, smooth 144 hz I miss so much. Thanks for your input, and if you think of anything else let me know!