Can you run a Dell PowerEdge server on 120v and 240v?

The short answer is no. At least on some of the newer Dell PowerEdge servers. There are some places online where it sounds like it may work with certain servers.

If you are running on 120v and then plug in a 240v line on the second PSU, the PSU light flashes 3 times and then stays off.

From the iDRAC we can see that one PSU Input Line Type is Low line (120v) and the other is High line (240v)

As a side note, the Input Wattage is different because we can pull more watts from a 240v line. Watts are Amps X Voltage, so halving our voltage, halves our total wattage.

Looking through the Lifecycle Log we see the following saying that the PSU is disabled because of a input voltage mismatch.

Alienware fan control in Linux notes

Helpful links

You can use the following commands to “initilize” the fans so the fancontrol can read them.

 sudo modprobe dell-smm-hwmon ignore_dmi=1
sudo sensors-detect

After that is done you should be able to setup a fancontrol config with

sudo pwmconfig

After it is set up you can launch fancontrol to control the fans

sudo fancontrol

If you want to tweak the setting, modify the fancontrol config under


or run pwmconfig again and replace config.

Sounds like you should be able to add the following to “etc/modprobe.d/dell.conf” to get it to run on boot.

options dell-smm-hwmon ignore_dmi=1

CPU stuck at 800Mhz or (.78Ghz)

Problem: CPU frequency is stuck at about 780 or 800mhz after waking up from sleep.

What causes the issue? Not sure what causes the issue, but seems to have something to do with unplugging the power adapter while putting to sleep or waking the system when it is pluged in after it was put to sleep on battery. Issue is random.

It appears that this issue can be temporarily resolved by disabling BD PROCHOT using ThrottleStop. Make sure the box is unchecked.

Download ThrottleStop from here

Things to try

Restart computer
Unplug and plug the power adapter in while computer is on
Put to sleep, plug or unplug power adapter, rewake up
Some other combination of the above.

More Info