To all with M2N78-LA CPU fan constantly changing speed [ Edited ]

[wb2001]

From the numerous posts there is a common factor,  the infamous M2N78-LA Violet motherboard.

If you have a BIOS version greater than 5.14, you will have this problem (according to my research).

It started with BIOS 5.16, and further BIOS updates have contained this bug.

(Added the next day, to clarify the question).

Numerous posts of this forum referenced that users had upgraded their BIOS. After that upgrade, the CPU fan started cycling up and down repeatedly. I took all those posts, and analyzed them, looking for a common point. All  users had the M2N78-LA Violet motherboard. The BIOS upgrade was 5.16 and greater.

Searching the internet with that BIOS number, I found numerous references to an apparent "bug" in the upgrade. The respondents were all looking for BIOS 5.14 to correct this problem.

[HRB]

I do not understand all of this information, but I can take my computer and this information to a repair place and perhaps they will. Thanks

[wb2001]

The difficulty is obtaining BIOS 5.14 to roll-back the BIOS.

[pclvr]

I have BIOS 5.18 and my fan had been doing this for months. I called HP to get a replacment while it was under the warranty and they gave me the run around saying it was fine.  I now have an issue with my brand new HD not being recognized under f9 even though f10 shows it.  So does this mean the MB is just no good and needs to be replaced or are there fixes for this faulty MB?

And has HP even noticed the issue and done any sort of recall? Have they done/said anything about selling this buggy equipment to consumers? 

VERY disppointed p6214y owner.

[humhead]

So what is the fix for this problem which started with an HP update?

[Big_Dave · Accepted solution]

Hi,

I have alerted HP to perhaps take a closer look at this issue.

[riotaYo]

It is very easy to solve just replace the fan.Maybe your fan is having touble in his "motor".It has no connection with your updates.

[cpwada]

I am experiencing the same ssue after applying the Motherboard update (5.16) using the HP Update feature on the weekend.  Now I hear the fan rev up and down constantly.  Very annoying.   We need to keep on HP to fix this issue.  Hopefully HP will acknowledge this and admit there is a problem.  Let's keep on them.

[falrgr4wsu]

I had this same problem with my P6320Y which has the M2N78-LA motherboard.  After I installed the bios update, my fan was very noisy and changing speeds.  I opened up my tower and found that the processor fan had a lot of dust built up behind it.  I removed the dust and that seems to have solved the problem.  Be sure to check your processor fan carefully and clean it thoroughly.  I was able to use canned compressed air but the dust was stuck on pretty bad and it took some effort to clean it up.  An air compressor might be needed in some cases.  I hope this might help others with this issue.  I don't know how the update comes in to play in this mess but cleaning the fan fixed the problem for me.  Give it a try.

[joshuaslocum]

This issue is not "solved". The inside of my machine and fans are dust free and the fan still revs every few seconds. It is the bios update that caused the problem.

Please see that a fix is supplied before it causes other problems. Thanks.