Recent linux-image update broke CPU fan

["Neal P. Murphy" <neal.p.murphy@alum.wpi.edu>]

I think the last linux-image update broke my CPU fan. OK, it didn't actually break it. But since the last update, my CPU fan (stock with vishera 8350 black) will NOT turn faster than about 3500 RPM.

I have been using fancontrol for months. It took weeks to get it set correctly. At maximum speed, I've seen (and heard) the fan turn in excess of 6500 RPM.

Until the recent kernel update, the CPU and case fans have ramped up with increasing temp and ramped down with decreasing temp. The CPU never exceeded about 60C when compiling linux using all 8 CPUs for 5 minutes. And that was with a mild overclock (4.4GHz, 1866 RAM at 2133).

Now, the CPU fan will not exceed about 3700 RPM. That's barely fast enough to keep 4 non-overclocked CPUs cool.

Has anyone else experienced this? Is it related to the kernel update? Or do I have a power supply or motherboard failing (again)?

Thanks,
Neal