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- Re: The HP 600 g2 mini has 901 rear fan error on 65w cpu's

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04-03-2022 06:07 AM
PC boots with 901 rear fan error whenever a 65w cpu is installed. I upgraded i5 6500t to i5 6500 and the system boots with 901 fan error every time. Keep in mind that only 90w power supply or above is needed for 65w cpu's. How can I fix this error as the cpu is supported on the 600 g2 mini. Please help.
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04-03-2022 11:05 AM - edited 04-03-2022 11:06 AM
Hi:
Below is the link to the HP Quickspecs for the Prodesk 600 G2 PC model series.
HP ProDesk and ProOne 600 G2 Business PC Series QuickSpecs (cnetcontent.com)
The list of supported processors by form factor can be found on pages 10 - 12.
Only the processors that end in a 'T' are supported in the 600 G2 DM.
That is why the i5-6500 is throwing a 901 rear fan error.
There is no fix that I know of other than to reinstall the i5-6500T.
If you want, you can upgrade to the i7-6700T.
04-03-2022 09:57 AM
Did you use the 65 watt cooler for the CPU? Very likely, the bios is checking the fan to see if the correct fan was installed.
I found the above by first looking here
https://partsurfer.hp.com/partsurfer/?searchtext=HP%20ProDesk%20600%20G2
and then picking a product ID that has the 65 watt CPU and looking for the cooler
Can you take a picture of the connector the fan is plugged into? If it has an extra unused pin then it may be possible to fool the system into thinking the better fan is attrached.
The warning message you mentioned was the rear fan. Maybe the problem is the rear fan cable is bad?
Possibly our expert @Paul_Tikkanen might be able to help with a better fix.
Thank you for using HP products and posting to the community.
I am a community volunteer and do not work for HP. If you find
this post useful click the Yes button. If I helped solve your
problem please mark this as a solution so others can find it
04-03-2022 11:05 AM - edited 04-03-2022 11:06 AM
Hi:
Below is the link to the HP Quickspecs for the Prodesk 600 G2 PC model series.
HP ProDesk and ProOne 600 G2 Business PC Series QuickSpecs (cnetcontent.com)
The list of supported processors by form factor can be found on pages 10 - 12.
Only the processors that end in a 'T' are supported in the 600 G2 DM.
That is why the i5-6500 is throwing a 901 rear fan error.
There is no fix that I know of other than to reinstall the i5-6500T.
If you want, you can upgrade to the i7-6700T.
04-04-2022 09:08 AM - edited 04-04-2022 09:10 AM
@G_man777 wrote:Thanks for the suggestions @BeemerBiker
Unfortunately, this motherboard doesn't have a physical rear fan connector on the board itself.
I had thought the same thought, that the bios is actually reporting the CPU fan is not the correct fan for the system but gave the back fan as the problem.
I have had several z400 motherboard and all complained or would not boot unless the original fan was on the CPU. A jumper to ground from one of the fan pins allows booting without pressing F1. There was also a wiring change to the 24 pin connector that was needed for my Z400s.
However, the 4 core 8 thread low power recommended by @Paul_Tikkanen is better than that CPU you obtained. I still think the bios can be fooled into allowing a boot with some type of fan trick.
Thank you for using HP products and posting to the community.
I am a community volunteer and do not work for HP. If you find
this post useful click the Yes button. If I helped solve your
problem please mark this as a solution so others can find it
04-13-2022 04:04 PM - edited 04-13-2022 04:12 PM
I was guessing based on my experience with a Z400 motherboard where I had to press F1 to continue.
This is the explanation of how to fool the Z400 quote
The Z400 performance heatsink/fan is HP part 463981-001, and its fan is a Delta AFB0912HH, with standard 4 wire PWM in/out of the motor. The 5th hole in the plug would be empty if it was a mainstream heatsink/fan, and is occupied with a ground jumper from hole 1 to 5 if it is a performance heatsink/fan. That is how the motherboard knows a performance fan is attached. It can't tell by current or rpms what is going on.....
I have no idea if this will work on your system. Is there a 5 pin socket for the fan with one pin unused? if not it wont work
Actual article is here
Thank you for using HP products and posting to the community.
I am a community volunteer and do not work for HP. If you find
this post useful click the Yes button. If I helped solve your
problem please mark this as a solution so others can find it