512 rear chassis fan not detected after replacing system board

[JJD123]

I have an Elitedesk 800 G1 that had a bad system board.  I replaced the system board and I get a 512 error stating rear chassis fan not detected.  There is and never was a rear chassis fan.  There is no place to mount one on this model.  How can I get rid of that error?  I can't find any such setting in the BIOS.

[wb2001]

@JJD123 ,

It is always helpful to state the exact model number and whether the unit is an SFF, Tower, or whatever.  Was this an exact swap out of the same motherboard?

[JJD123]

It is a SFF.  The replacement is from HP and appears identical except for the connecter for the chassis fan is not on the original.  The spot is labeled but the connector is not there.

[wb2001]

@JJD123 ,

Here are the part numbers.  Look at the board you have NOW, and look at this document.  Is this the correct board for the SFF ? The Desktop board is a different number. and it does have a rear case fan connector.

http://h10032.www1.hp.com/ctg/Manual/c04331008

[wb2001]

@JJD123 ,

You gave me a KUDO, and it is deeply appreciated, but what did you find out ??  

Which board number/version do you have? 

The SFF w/o the fan header, or the desktop board with a fan header?

[Uncas]

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@JJD123 wrote:

I have an Elitedesk 800 G1 that had a bad system board.  I replaced the system board and I get a 512 error stating rear chassis fan not detected.  There is and never was a rear chassis fan.  There is no place to mount one on this model.  How can I get rid of that error?  I can't find any such setting in the BIOS.

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Hi,

I have an HP h-9 1135 Pavilion and recently saw your post.  My OS is Windows 7 (64-bit) Professional, Service Pack 1.

My story begins at the time I was getting Microsoft updates in 2015 for Windows 7, when I noticed I was suddenly getting the same error message stating, 'rear chassis fan not detected'.  I searched for months on this site and Microsoft's for solutions.   I even checked those offered on YouTube. None of them worked.  My fans all functioned when the computer was on, without the cover, and there were no loose wires or connections. I even replaced the old fan with an identical model. And Zippo. Nada.  Still got the same inane error message. I even contacted HP 'Smart' Friends for assistance and how clueless they were.  They talked me into doing a 'system recovery' which was an absolute fiasco. Finally, for my own sanity, resigned that this was a red herring that no one could solve, I downloaded the CPUID HW Monitor to check my actual fan speeds periodically.

Fast forward to the present. I had an old PC game, MOH Allied Assault that I was trying to load on Windows 7. The game came out in 2000 and Windows XP was the last OS that supported the software. It was 17 years since I last played it, too. I thought it odd that I was able to load much older games with Windows 7 but not this one, so refusing to give up and toss the game, I came across a YouTube site for gamers trying to run old PC games such as MOH Allied Assault on Windows 7. 

https://www.youtube.com/watch?v=IzblNgrmpMs&t=3s

In the video, it explained why the game would not run from the original game CD. It seems Microsoft performed a ‘security update’ back in 2015 that created problems for the drivers for some of these older games as they were no longer backward compatible.  I simply followed the directions on this video, made the adjustments in Windows 7 via command prompt and then I was able to run MOH Allied Assault and the expansion pack, Spearhead on my computer.

Then when I restarted my computer, voilà, the infamous error message that appeared for every restart since the 2015 update was GONE! And no longer was I prompted to hit F1 to continue.  My computer is now as it was in 2012 when I first pulled it out of the box and fired it up for the first time.

I wanted to go back to Microsoft’s community support site to report the finding but now it seems every thread concerning this subject is locked for further comment. What a coincidence?

Well played Microsoft!