Elitebook 840 G5 i7 CPU stuck at 0.4GHz after BIOS update to version 01.26.00 Rev.A

[MattMieszko]

Hello,

I bought a refurbished laptop and performed all drivers and software update on it, including BIOS update. After that update the CPU in BIOS is showing only 400MHz (it's intel I7 with 1.9 GHz). 
I tried the following steps:

1. Restore windows System FIrmware driver to older version - did not help

2. Reinstall BIOS - did not help

3. Unpin fan - did not help, fan was still running quietly at low RPM

4. Unpinned CMOS battery, removed both RAM sticks = FAN started working on full RPM for a while so it is probably working fine. I moved RAM between slots, tried booting with first, booted to Windows fine, tried with second only, also booted fine but the CPU stayed at low frequency

5. Looked around internet, found the BIOS recovery procedure with key combination of Win+B or Win +V = did not seem to work because of HP Sure Start

So right now I was wondering if it is possible to download older BIOS versions or HP Firmware Packs older than Q78 (for Win 10 22h2). I could also try booting older windows, but I doubt the issue us there. For some reason the CPU entered overheating prevention

[BeemerBiker]

I looked at the bios simulator for your system since I do not have 840 G5 and there does not appear to be any thermal or speed monitoring.  

Lets see if the CPU or system has a problem before windows starts up

Tap the ESC key after powering on to run diagnostics. Do not allow any updates if disk or memory fail.

Did system pass?

Download and run memtest86 and look at the CPU speed and temperature. 

https://www.memtest86.com/

If the CPU temperature and speed seem OK in bios then try resetting the Windows CPUs

Bring up the device manager, select Processors, right click and uninstall every core listed for the processor.  Do not reboot until all have been uninstalled

Lemme know if still a problem.

[MattMieszko]

Hi, thank you for the prompt response- I’ll do that first thing tomorrow and post screenshots here.

[MattMieszko]

Unfortunately no success, tests passed, CPUs uninstalled but still showing 0.4GHz in BIOS and Win

 

 

 

 memtest86 in progress

[MattMieszko]

Memtest booted fromUSB shows more MHz than BIOS and CPU tem goes up to 45

[BeemerBiker]

The different speeds are suspicious.

Was there a problem with the speed before the bios update?  If there was no problem the the bios update was bad or the CMOS needs to be reset (step2  below) but also the "win + v" key in step 3

Your system has  "sure start" as described here

https://support.hp.com/in-en/document/ish_3932413-2337994-16

You may have done step 1 but try 1 and 2 anyway

Step 3 mentions the WIN + v key.  That should also reset the CMOS.  Try this before the "b" key.

If the above do not work then try the key press recovery.  If you get the option, chose an older bios before 1.26

[MattMieszko]

I tried option 1 and 2 with CMOS reset and option 3 is apparently not supported by computers with HP Sure Start, but I did it anyway making sure to follow this instructions https://youtu.be/qpiGUojtr3E?si=H4pFs8ySDEIGn0yR

unfortunately: no go.

the only option seems to be to restore BIOS from USB but I don’t have a similar computer with older version installed - maybe there’s another way to create such disk and try older versions of BIOS?

kind regards,

matt

[MattMieszko]

Was there a problem with the speed before the bios update?

No, I bought it as refurbished and after I did batch update from HP Support Solution app, it slowed down

[BeemerBiker]

I just looked at bios version 1.22 dated Nov 8, 2022 and read the following in "Bios Flash.htm"

This Firmware Update SoftPaq contains utilities and data files for restoring or upgrading the firmware on HP business notebooks

possibly you can restore the firmware to late 2022

https://ftp.hp.com/pub/softpaq/sp143001-143500/sp143245.exe

please read the instructions in that htm file

Startup Menu / F10 Setup Firmware Update

The HP Business Desktop systems provide a firmware upgrade option through both the Startup Menu and the F10 Setup application. using the "Update System BIOS" link.  Reboot the PC and press the Esc key to display the Startup Menu. Select the "Update System and Supported Device Firmware" menu option directly for an immediate update from media (see below).   Alternatively, select "BIOS Setup (F10)" or reboot and press F10 to access the BIOS Setup utility. In the Update System BIOS menu, select "Update System and Supported Device Firmware Using Local Media".

These methods require that the firmware binary file is present on USB media or the hard drive in a specific folder - either "HP\DEVFW" or "EFI\HP\DEVFW" will support this feature. The file must be named 'firmware.bin'. The HP Firmware Update and Recovery utility has a feature that will copy the image file to the correct folder on a USB device for you.   If no firmware file is found on USB media, the system will look for a firmware file on the hard drive.   If a BIOS administrator password has been set, the password will be required before being able to access the "Update System BIOS" menu or BIOS Setup.   The firmware update will not be complete until the system is restarted.

[MattMieszko]

Thanks, and apologies for delay - I'll check it out on Monday, 19.02 as I currently don't have access to the device