PS/2 keyboard doesn't work after BIOS update

On an Asrock B450 Pro4 I had to reset the BIOS to defaults to get Instant Flash to work so it would update from 10.43 Beta to 10.60

I also installed a LPC TPM 2.0 module.

I got everything configured how I wanted, but upon booting to Windows, my PS/2 keyboard doesn't work.

I went back to BIOS and switched the PS/2 Y cable setting from Auto to Enabled. Still no keyboard in Windows.

But hitting F2 or Delete on the PS/2 keyboard during POST works to get into BIOS.

The Start DWORD is set to 1, Hexadecimal, in Computer\HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\i8042prt

I also uninstalled the Standard PS/2 keyboard driver and restarted. When Windows starts *it turns the numlock light off* on the PS/2 keyboard.

The Registry settings shown in this video are as they should be


This command to launch troubleshooting has been deprecated msdt.exe -id DeviceDiagnostic

Fast Startup is already off.

"To access the Windows Keyboard Troubleshooter, right-click the Start button and select Settings. Go to System > Troubleshoot > Other troubleshooters, locate Keyboard, and click Run." Microsoft has removed the keyboard troubleshooter!

If you have something to try NOT already listed above to try, I'd love to know it.

So I'm having to use a cheap USB keyboard with Windows. Why can't someone write a small program to forcibly fix this? Call it MakeTheDamnPS2KeyboardWork.exe

@Galane

I don't know the solution to your problem, but...
If it were me, I'd just get a USB keyboard.

PS/2 has its advantages over USB. And if the KB is nice, why replace it. I would not give up just yet...

Something must have borked up Windows after the BIOS upgrade.

Did you already try a full BIOS reset after the upgrade? Sometimes this is mandatory. Also Disable fast startup in Windows.

Try without the TPM module, which isn't actually needed.

SlicEnDicE said:

Did you already try a full BIOS reset after the upgrade? Sometimes this is mandatory. Also Disable fast startup in Windows.

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I had to reset the BIOS to be able to update it. Shouldn't need to reset it again.

stormy13 said:

Try without the TPM module, which isn't actually needed.

Click to expand...

fTPM with the CPU can impact performance a bit

The way it's disabling the keyboard is quite like how it did a lot of people with the initial release of the 25H2 update that trashed many installs of Windows. Tell the user to hit Enter to continue to attempt recovery, right after shutting down all PS/2 and HID input, and after the user had already told Windows to attempt recovery.

PS/2 keyboard support should be one of those things that is *impossible* for an OS to f@ck up. It should be baked into the system in such away that ist *works* and absolutely nothing can stop it working nor get in between the input and the OS. Microsoft has only had 39 years to get this right...

Galane said:

I had to reset the BIOS to be able to update it. Shouldn't need to reset it again.

Click to expand...

If you read recommended practice for BIOS updates, most MB manufacturers recommend a reset after upgrade. Especially when there are issues.

Sounds like your interrupt tables got borked up after updating from an experimental BIOS. UEFI firmware is like a mini-OS, it needs recovery sometimes too.

You have 2 options:

1. Follow recommended advice given for troubleshooting and hopefully resolve this issue

2. Ignore everything and go purchase new hardware.

The ball is in your hands.

Have you plugged the same keyboard into a different PC, as a sanity check? Then you know if it's the PC, Windows (same Monthly Update) or the HW.

garlin said:

Have you plugged the same keyboard into a different PC, as a sanity check? Then you know if it's the PC, Windows (same Monthly Update) or the HW.

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They already stated that they can get into the BIOS, so I doubt the KB is the issue. Does not hurt to try though.

SlicEnDicE said:

If you read recommended practice for BIOS updates, most MB manufacturers recommend a reset after upgrade. Especially when there are issues.

Click to expand...

This is exactly what I do after every BIOS update, I do a Reset this PC, keep personal files, just a fresh cloud download of up to date W11. Never have any issues. I appreciate that would be an absolute nightmare for some folks or just too much trouble.

there is an adapter from ps/2 to usb. but, I don't know if it will work for you (I have one). I still have an original ps/2 M.S. Ergonomic keyboard (very large). I can't use it anymore because most of my computers do not have a ps/2 connector on them. If you can find one cheap, maybe ebay, you can try it.