[Guide] BIOS Update on Probook 4x40s (and other Probooks?)

Sep 27, 2015
HP Probook 4740s, 4540s
HD 4000
Updating HP BIOS can be very frustrating. This worked for me on a Probook 4740s.

1. Download the update from HP site.

2. Unpack the servicepack ("spNNNNN.exe", NNNNN=Service Pack Number) with any unpacker, e.g., Keka.

3. Unpack the Rom.CAB that is in the unpacked service pack.

4. Rename the generic file names from HP (below) with the Type for your machine. You can get the type from the screen displayed in BIOS settings under "system information". For the Probook 4x40s it's "68IRR", so:
efibios.sig ➔ 68IRR.sig​
Rom.sig ➔ 68IRR.s12​
Rom.bin ➔ 68IRR.bin​
Do not confuse the two .sig files. Identify them with their different file sizes.

5. Format a USB stick with MBR and a FAT32 partition (GPT may also work-?).

6. Create the folder structure below on it, and copy most files from your unpacked service pack and CAB into it, like shown below:


7. Keep the USB stick plugged in.

8. Reboot and enter BIOS settings (press F10 on boot).

9. Select the BIOS update checkbox.

10. Leave BIOS Settings, saving changes.

11. The machine will reboot and start the BIOS update program. Hopefully...

12. Follow the displayed instructions to update.

13. When the update is finished, the machine will reboot automatically.

14. Done. Boot into OS as usual.

If the update fails, look into your USB Stick for a log file for more info on the reason.
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