# Irritating whine in new 9.0 install



## davidgurvich (Dec 6, 2010)

Every once in a while I test various operating systems on an older problem laptop that I have(thinkpad X30:1.2GHz P3,1GB ram, i830 graphics).  So far FreeBSD has not worked well on it.  Suspend/resume fails and other issues including slowness in switching between programs and a completely unworkable wireless.  These are all issues that don't exist on PCLinuxOS or OpenBSD.  

This past week I decided to see how ZFS and other things are working with FreeBSD-9.0.  Almost immediately after installing I couldn't wait to get rid of it.  There was an annoying high-pitched whine that I couldn't stand.  I tried ataidle and a number of other settings but nothing worked.  I thought it might have something to do with the fact that I haven't disabled WITNESS or debugging in the kernel.

Turns out that the kern.hz setting was 1000.  Setting 
	
	



```
kern.hz=100
```
 got rid of the irritating whine.  

As a side note the problems that plagued wireless and networking in general and caused me to stop using FreeBSD seem to be better.


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## shepper (Mar 2, 2013)

I had this same issue in an old laptop based on an Via C3 800mHz cpu.

My searches in this forum and Google indicated this is a common solution and that performance does not usually suffer.  My question is what am I actually setting? It does not seem like my single core CPU is running at 100Hz which would be the cpu clock speed.  Does it have to do with the memory?  I think the laptop has PC133 memory.

2nd Edit:  I found this link.  It is an interrupt and appears to have a significant affect on power consumption.


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