PC fails to power on via BIOS after turning on Secure Boot. Assistance needed!
PC fails to power on via BIOS after turning on Secure Boot. Assistance needed!
I reinstalled Windows by turning off CSM support and restarting back to BIOS without issues. Some users recommended enabling Secure Boot, which I did using the default Gigabyte platform keys. At first, BIOS didn’t open but stuck on code 78 (ACPI initialization). When I powered it off and on, it would turn on and I had to press F2, F12, and Del repeatedly. Now every startup shows code A9 (Bios setup started) even without pressing any keys, and the screen remains blank. Can someone explain why this is happening?
Try resetting the CMOS if you can’t locate the pin in your guide. Consider using a coin cell battery for a short time to test the connection. Be cautious with websites and ensure your antivirus is current—Secure Boot isn’t essential for most systems. For certain bootable tools, disabling it might be required (as I discovered when setting up Ubuntu Server in a HyperV VM). If the system functions without it, keep it off. This method stops unauthorized access during startup, though it’s not a common issue for regular users. More frequent threats like viruses, malware, and worms are better managed by your antivirus software.
He suggested checking the situation if you can't boot Windows. Even if the BIOS isn't showing up, the issue might be with the power connection or the CMOS battery. The CMOS pin is labeled, and the manual mentions using a screwdriver or paperclip to short it temporarily. Since you're hesitant about damaging the plastic connector, you could try a quick test with a paperclip for a short time. If that doesn't work, waiting a day or two might help, or you could bring in a technician. Alternatively, unplugging the PC and connecting a paperclip to the pins for five minutes is another option.
Typically, when Secure Boot is active and detects an issue, a warning appears about a page. If your whole system can’t start properly, it might suggest another problem exists. Have you ever unplugged your storage devices to test if you could access the BIOS again?
Well I don't think the issue is resolved because my system was legacy, CSM support was off, and the UEFI was a bootable USB. The boot loader should have ignored the SSD/HDD and only checked the USB, but I already tried removing it. After some research, I suspect custom platform keys in Secure Boot settings might be the cause—I chose the Gigabyte default PK and didn't expect that to be the problem. Now I'm unsure. Can resetting CMOS disable Secure Boot or at least reset the platform key settings? Also, just a note: I just found something interesting! The LED codes changed when I plugged the USB back in—no boot, but the codes were different. Without the USB it was stuck on A9 with BIOS setup started. It showed no BIOS, but with the USB connected it displayed 78, indicating ACPI initialization. So Secure Boot might be involved here. What do you think?
Reverting CMOS will return your BIOS configuration to its original factory state. When secure boot is turned off by default, it will also reinstate that setting.