I see 92mm case fans for the XPS 8500 listed on "fleaBay". Some are used, and here's one claiming to be "new open box".

CAVEAT: Don't know any of these sellers, so do your homework...

If you just want a cheap used fan, https://www.ebay.com/itm/HP-Foxconn-92mm-Brushless-12V-0-4A-4pin-Cooling-Fan-435452-001/233821147955?epid=14040482768&hash=item3670d39333:g:El8AAOSwJSlfSBT5

If you prefer a premium fan, https://www.ebay.com/itm/NF-A9-PWM-92mm-Premium-Fan-Unopened/254814611311?hash=item3b5422676f:g:wEoAAOSwloxf4U4I

4 pin fans can be plugged into motherboard 3 pin header, np.

Hello,

Thanks for your response. Just wondering about the Noctua fan you provided a link to. Do you know specifically if it will work as the OEM fan does? I understand now that connecting it is no problem but, I have tried a bgears b-blaster 90 3-pin and it only ran during post for a short time. Then it shut down and would not run again. That's when I found a post on the forum that it needs to be a Dell specific fan or it would not work.

Thanks!

@redxps630 -  Why would @Knash63 have gotten a "fan failure" error at boot if BIOS doesn't monitor/control the chassis fan in the XPS 8500?

I presume the OEM Dell chassis fan has been reinstalled and is working without any additional fan failure messages, implying the motherboard doesn't have problems seeing that fan.

But yes, I agree, best to go with another Dell OEM chassis fan to avoid further issues.

And I wonder:

1. Was that fan failure error caused by the CPU fan connector being accidentally dislodged from its motherboard header during installation of the new chassis fan?
2. Did the b-blaster fan simply die so it doesn't even start up now... ??

agree that bios monitors chassis fan rpm on the 3 pin header.  often times when non Dell oem fan rpm response is out of limits of what BIOS considers normal it throws an error msg on startup. question is why OC's fan replacement stops spinning. afaik xps bios does not stop chassis fan from spinning.  it does not have such control in its design.

the other possible explanation for error in OC case is that the replacement fan is not working, or the 3 pin header is defective and fails to deliver 12V to the fan.  In both hypothetical situations the fan does not spin to a reasonable rpm (it stops after feeble spin) and it is natural that bios sends an appropriate error that fan has failed.  If the header is bad then any replacement fan would not work.

@redxps630  - @Knash63  has to tell us if reinstalling the OEM chassis fan works.

The OP says "...before the original one fails" so my presumption is it was working and should work again when reinstalled, unless the motherboard header has actually failed...

Ron,

Yes, I reinstalled the original and it is working properly. No errors on startup. It does run at a constant speed. I thought I'd replace it before it decides to go. I will stick with an OEM fan when I  decide to try again. Trying to sell the bgears fan I bought first. The CPU fan runs perfectly and I have had no issues. The bgears fan ran at startup the three times I rebooted with it installed so, I assume it does work as it's supposed to in a different system.

Thanks for your input.

Hey, I did the same thing and it's working perfectly for me, thank you.