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HP Recommended
HP Eliteone 800 G3 23.8’’ Touch AiO.
Microsoft Windows 10 (64-bit)

Hi All.
Can anyone please help with the problem below??
Post error, CPU Fan Detection Error 900-CPU Fan not protected.

Post error, CPU Fan Detection Error 900-CPU Fan not protected (CPU temp only 35C) Press enter to continue. PC booted into W10 no problem, the CPU fan was running at max RPM then returned to normal RPM after about 8mins. I would point out that this Error has happened on previous occasions but I did not think much about it. (May be a W10 up date???).

On 12/10/2019 on power up/boot I received a Post error, CPU Fan Detection Error 900-CPU Fan not protected.
Power up 2/11/2019 CPU Fan Detection Error 900-CPU Fan Not Protected CPU (CPU temp 35C) fan at max RPM, PC was restarted Error 900, fan max RPM then eventually returned to normal RPM.

19:20hrs 3/11/2019 CPU fan started running at full RPM CPU temp 45C. Power down at 19:28hrs power up 19:30CPU Detection Error 900-CPU (CPU 34C) Fan at max rpm until shut down of PC at 20:15hrs.
3/11/2019 to 4/11/2019 PC running all night (AV and Malware scan) after restart on the morning of 4/11/2019 straight into CPU Fan Detection Error 900 CPU temp 39C fan at max RPM at 11:00 fan still max RPM.

4/11/2019 at 11:00 PC powered down 11:05 PC power up CPU temp 35C once again CPU Fan Error 900 and fan at max RPM.
4/11/2019 PC powered down at 11:40 PC power on 12:45 Post error 900 CPU fan max RPM at14:00 still at max RPM. CPU 32C.
Any help or advice would be very much appreciated.

UPDATE.
04/11 2019 HPPC Hardware Diagnostics tool installed an all tests run PC passed all tests.
04/11/2019 at 19:30 hrs PC Powered down CPU fan still running at max RPM.
05/11/2019 at 08:30 hrs power on Post error 900 CPU fan running at max RPM
Unable to enter self-test or BIOS via keyboard due to Post error.
Again any help or advice would be very much appreciated.
Regards,
Russ.

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