Computer doesn't POST after enabling Secure Boot

I wanted to enable Secure Boot to check if my PC Is compatible with Windows 11, and in order to do that, the UEFI firmware asked me to choose a Protocol/Publisher/Platform key (I don't remember exactly). I choose the default one (I think 808 pk), then disabled CSM Support, and now it doesn't boot, with the display remaining black and the keyboard LEDs flashing on and off.

• I tried everything I saw on the internet:
  • reseated CPU, RAM, and GPU
  • disconnected hard drive and connected an older one [10+ years old]
  • tried another GPU [10+ years old]
  • reset UEFI firmware with the jumper and unplugged CMOS battery overnight
• Specs:
  • MB: Gigabyte H410m s2h
  • CPU: i3-10100f
  • GPU: GTX 1650
  • RAM: 1x 8GB DDR4 2666mhz (HiperX Fury CL16)
  • PSU: Elementium Silentium E2 550w 80 Plus
  • HDD: Western Digital Blue 500GB, 7200rpm

How do I troubleshoot this?

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5 Answers

Boot the computer without any drive connected. You should be able to access the "BIOS" (or actually UEFI setup) and revert the changes you've made. Then connect the drive and boot into Windows.

Check if your drive is partitioned using the GUID Partition Table (GPT) or Master Boot Record (MBR) style. You can do this in the Disk Management console accessed by right-clicking the Start button, by right-clicking the drive (not partition) and selecting Properties.

If it's MBR, you'll have to use the mbr2gpt utility to convert it. Secure Boot requires UEFI boot mode and Windows supports UEFI boot mode only on GPT drives (at least officially). You're probably booting in BIOS mode currently, and forcing UEFI mode only with Secure Boot breaks your system.

Once you're on GPT, enabling Secure Boot should be safe - Windows's default UEFI boot setup is Secure Boot-compatible. You shouldn't have to set up UEFI keys manually though. Just turn Secure Boot on and leave everything else on defaults.

5

TheIntel® Core i3-10100F Processordoesn't have integrated graphics, so I believe that you were depending for display on the GTX 1650.

It seems that the BIOS has lost the ability to use the GPU, so what you now have is what is called a headless computer.

The only idea I have is to replace the CPU by another with integrated graphics, to be able to enter the BIOS/UEFI.

If you don't have one available, no matter how old it is, taking the computer to a repair-shop could help.

2

try disconnecting the power from the back, take out the battery from the motherboard and then wait for a few minutes. then pot the battery back and plug it back in and it should work

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What you should do is restart to your BIOS default settings.

1. Unplug you PC power and ethernet cable.
2. Press/hold the startup button for 15 seconds.
3. Open your PC, find and then remove the motherboard battery (might be located under the graphics card if you don't see it).
4. Press/hold the startup button for 30 seconds.
5. Re-install the battery
6. Open you PC! Be sure to only plug in mouse, keyboard, monitor and power cable.

Same happened here. Altough I have Gigabyte B450 S2H motherboard which does not have any bios jumper for reset function. So luckily I had a programmer clip and programmer clip adapter and programmer USB stick device for bios chip programming. The device is not expencive and it goes on the chip, on the circuit board. I have other computers also, so I used some usb extension cable to reach the spot. Not everything well happened since pins of the device short circuitted trough the pin of bios chip and some electric burn out smell came out. Transistor I quess, since it still worked LATER. It is not much space to make the clip on the chip but finally I did it after maybe 50 try outs. There was brand new bios update file for the motherboard at the home page of the motherboard so I just clipped the chip, detected it, and took some reading out of the orginal (but bad bios setup settings) chip. Since I was sure about the device, I just opened the bios file for the program and started the programming by clicking the write function button. Now it was falshing/programming/typing and what so ever installing the brand new bios version on the chip. Since it was suppose to be there, I had to read the chip again to be sure about the result of former programming/flashing. Ok. It was there and everything worked like charm again. Altough all settings are naturally at default since the new bios file flashing installation. So you might have no other way to make it right. It's not too weird or expencive but it takes time to order clip, cord, adapter part, and programmer. Also the program has to be asked from the seller. Those devices are sold at eBay, and AliExpress. You could find the price less than 10$, and arrival period 1-2 months. About the clip, I would say it's not long lasting, and you need super extra care for placing it right, since short circuit is possible if it's not placed properly. The flashing program has 'detect' button, so the connection may be checked rapidly. The program will show the type of the chip (8pins BIOS chip usually) if 'detect' button is pressed. That's what I did, and maybe some others also. It was not too hard thing to do, but yes, I studied information technologics in academical school of professional education degree, so I have some experience and knowledge for success. I bought that clip long time ago and I've used it on few devices and yes, graphic card bios of few cards went correct by that. That's last and the most pro method to fix a program problems out from healthy chip. ... job

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