CPU fan speed control fails?

[JaroMehesJr]

Hey guys,
I got a Z87P-D3 motherboard which I love.
It's 100% stable, never got a BSOD or anything.
However, recently I noticed sometimes the auto fan speed control just fails and doesn't increase the RPM according to CPU load.

To make it short and clear, there are two scenarios; normal (most of the time) and strange (sometimes).

Working normally:
CPU cooler rests at around 1000 RPM, SpeedFan shows about 33° C.
Then when stressed (for example Prime95) as the CPU load goes up, the fan speed increases to 2000 RPM or more.


Abnormal:
This happens only about once a month, usually after several sleep/wake cycles:
The CPU fan speed is constant, around 1200 RPM and does not increase even if I run Prime95.
The temperature climbs up to 75° in HWMonitorPro, however, Speedfan shows -128 (obviously wrong).

Good news is, this happens once a month and after a simple reboot everything Works fine again.
So this doesn't cause me any trouble, but anyway  I was curious what this could be?

Cheers

[autotech]

Let me put it this way, It is a computer and should be shut down and restarted at least once every 5 to 7 days. This causes the memory to dump and start over.  Once the memory gets full or wrote over so many times it can cause lil problems like this. Which is why when you restart it is fine.

[JaroMehesJr]

Let me put it this way, It is a computer and should be shut down and restarted at least once every 5 to 7 days. This causes the memory to dump and start over.  Once the memory gets full or wrote over so many times it can cause lil problems like this. Which is why when you restart it is fine.

Agree, this is absolutely true.
However, the issue doesn't seem to be memory related; it happens even if I enter sleep mode a couple times in a row right after clean reboot.

[JaroMehesJr]

Wow. Disabled ErP in BIOS and seems to be fixed. Have to knock wood, though.

[JaroMehesJr]

Update: happens anyway, just less frequently.