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jr90
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z420 reset loop after BIOS v3.91 update

z420
Microsoft Windows 10 (64-bit)

Hi how are you. I have been reading the forum in search of a solution for my z420.

 

I recently updated my BIOS to v.3.91 under windows 10 with the HPQFlash utility. When the update had completed, windows gave a a blue screen with an error message saying the system needed to restart.

 

Once it restarted it went straight into a reset loop with the same symptoms described here:

 

https://h30434.www3.hp.com/t5/Notebook-Boot-and-Lockup/Reboot-Loop-No-BIOS-screen-shown/td-p/300368

 

 

 

I know from the maintensnce PDF the designator E15 is the ROM bootblock recovery header.

When I place the jumper on pins 2-3 I get the reset loop, the system reboots every second constanly. If I place the jumper on pins 1-2 it just switches on without video output to the monitor and after 1 minute the fans start to spin a full speed.

 

Same as described here:

 

https://h30434.www3.hp.com/t5/Desktops-Archive-Read-Only/HP-Z420-BIOS-Upgraded-Now-workstation-will-...

 

 

 

http://h20628.www2.hp.com/km-ext/kmcsdirect/emr_na-c03424977-1.pdf

 

 

I would appreciate any help you could give me.

 

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