Optiplex 755 fan speed

Are you trying to speed up the fan to cool the processor? Dell bios does this automatically. It senses the processor is running hot and it will speed up the fan to keep the processor at a stable temp.

I am actually trying to slow it down to make it quieter actually. It's because the system is always idle.

Thanks.

I have several Optiplex Small Form Factor 755, 745, 620 and I notice when I loaded some 3D screensavers the fan would kick into high speed and make a ton of noise. So, I had to remove them from the desktops. If you have Optiplex Small Form Factor 755 it only has one fan in front to cool the processor and to vent all the hot air out the back of the case and one small fan under the hard drive and that is it. I think these PC's are made for the simple day-to-day duties and not to run any heavy processing power like games or CAD work.   

Sniffles

Try reseating the CPU and the fan plug.

One time when I had a GX620 I accidentally spilled some thermal paste into the LGA775 grid which would make the fan take off like a rocket ... make sure everything is clean

You might need to call Dell and have them send out a new fan. The fan might be dieing or its just a noisy fan.

Sniffles

The only way I know how to slow down the fan is to reboot. That what I tell my users. Also, make sure you have the latest Dell Bios

Release Date:  6/20/2008

Version:  A10

Download Type:  BIOS

File Format:  Windows/DOS

File Size:  2 MB

I did a google search and found this free software.

 http://www.diefer.de/i8kfan/index.html 

 http://www.almico.com/sfdownload.php

I also found this forum on tweaking your computer they might be able to help you. http://www.tweaktown.com/

Did you see in the Settings > Options of SpeedFan, the option "Active Dell Support" ?

Works fine here, in SpeedFan 4.49 and Optiflex 755 SFF. 

These quiet down all dell models.

http://www.bestbuy.com/site/bose-quietcomfort-15-acoustic-noise-cancelling-headphones/9450578.p?id=1218106625357&skuId=9450578