HP Compaq Elite 8000 Convertible Minitower 512 Rear Chassis Fan Error

[McJones]

So I purchased my Compaq 8000 Elite secondhand from a liquidated company that used to run their computers hard for years in early 2020 as the primary computer for an arcade cabinet I am building. However, I noticed the rear chassis fan was starting to get loud and sounded like the bearings were starting to go. So, I pulled the fan, and installed one of my spare 92mm Noctua brand fans to keep it cool and quiet. After doing this, however, the computer started booting to a "512 rear chassis fan not detected" error. Naturally, since I've already learned this unit does not like anything not HP branded when I tried to replace the RAM (gave a motherboard failure beep code when new RAM was installed), I went ahead and installed the old fan again. Now, it consistently boots to that error message. What is weird is that the fan is very much on, and the computer ramps it up to full speed over a period of 45 seconds after post error.

Here's what I have done so far:

- Disassembled and reassembled unit

- Cleaned contacts

- Updated BIOS

- reinstalled drivers (drivers were missing in my Windows install)

It is currently at my work getting looked at, but they keep turning it off because of how loud the fan is at full run. What can I do to resolve this? There's nothing in the BIOS that allows me to turn off a presence check on the fan.

[itsmyname]

@McJones -- the web-site: www.crucial.com gives good advice about which RAM (manufactured, of course, by Crucial) would be compatible with your computer.

In regards to the fan, I would remove the original fan, and connect any other case fan, and just ignore the error-message every time that you restart the computer.  Which is more annoying -- the noise from the fan, or clicking "OK" to that error-message? 

Or, search on eBay or Amazon for a "genuine" HP fan that the motherboard will accept.