-
×InformationNeed Windows 11 help?Check documents on compatibility, FAQs, upgrade information and available fixes.
Windows 11 Support Center. -
-
×InformationNeed Windows 11 help?Check documents on compatibility, FAQs, upgrade information and available fixes.
Windows 11 Support Center. -
- HP Community
- Notebooks
- Notebook Software and How To Questions
- Re: Force downgrade probook 4520s bios from f.61 to f.21>

Create an account on the HP Community to personalize your profile and ask a question
03-02-2022 04:21 PM
Hi. I've updated my bios to f.61 and it cannot control fan speed properly. (above 100C and FAN speed doesn't increase). I am certain about air vents and thermal paste quality. so I want to downgrade my bios version before f.21.
Regards
03-02-2022 04:40 PM
Hi:
Unfortunately, the release notes for the F.61 BIOS update indicates that after that version is installed, you can no longer roll back to any previous versions.
https://support.hp.com/soar-attachment/808/col40300-ob-167591-2-ob-167591-2_sp75888_releasedoc.html
NOTE: Due to security changes, after installing this updated BIOS, older versions cannot be reinstalled.
03-04-2022 08:25 AM
Well I know this. That's why I'm asking in a forum. this version of bios have buggy FAN speed control and the temporary solution is using software or scripts to manually speed up the fan! without them fan speed doesn't increase and sometimes temperatures over 105 can be seen. We don't have hope for new fixed version by hp! so I'm asking about options that we have. perhaps even hardware level chip program to downgrade the bios?