Lemur (lemu2) Fan Speed Doesn't Throttle

Bug #640842 reported by Thomas Aaron on 2010-09-16
This bug affects 2 people
Affects Status Importance Assigned to Milestone

Bug Description

The fan on the Lemur 2 (LemU2) doesn't throttle.
Probably affecting battery life as well.

Determined to be a BIOS issue. Confirmed by in-house testing.

Changed in system76:
status: New → In Progress
Thomas Aaron (tom-system76) wrote :

Instructions for flashing the BIOS in the LemU2 to improve fan throttling.

You will need two USB flash drives for this procedure.

1. Make sure your Lemur is connected to AC power.

2. Download the freedos image from the post below this one. Click the Save button. The file will be saved in your Downloads folder.

3. Create a bootable FreeDOS flash drive...

* Open a terminal and run the following command...
    tail -f /var/log/syslog

* Insert USB pen drive #1.

* In the terminal, syslog will give you the /dev/* path of your USB pen drive. Record it. It will probably be /dev/sdb1. It is of the utmost importance that you record this path correctly.

* Now press Ctrl-C to return you to a command prompt.

* Now run this command in the terminal...
    cd Downloads

In a terminal, type:
  dd if=~/Downloads/Sys76_BootImage of=/dev/sdb bs=1M
  NOTICE that I omitted the number from the USB path (i.e. /dev/sdb instead of /dev/sdb1). ALSO, if you recorded something other than /dev/sdb in step #3, you should substitute your recorded path (minus the number) for /dev/sdb. In other words, type:
dd if=~/Desktop/Sys76_BootImage of=<your usb path minus the number> bs=1M

* Right-click on the USB pen drive icon on your desktop and select EJECT or UNMOUNT.

4. Install Firmware Files on a Second Flash Drive...

* Download the firmware files from two posts down... below the post with the FreeDOS image.

* Insert a second USB Flash Drive.

* Unzip the firmware file into the second USB flash drive.

5. Flash your firmware...

* With both USB flash drives plugged into your computer, reboot and boot into the FreeDOS drive. To do this, press F1 during the Sytsem76 splash page to enter a boot menu and then select your FreeDOS drive. If this doesn't work, you may need to Press F2 during the System76 splash page to enter the BIOS Setup Utility and set "USB Device" as the first boot device in the boot order. If you need assistance with this, please do not hesitate to call System76 technical support.

* Once you've booted into the FreeDOS flash drive, please run the following commands one at a time, pressing enter after each one.


Once the firmware has been flashed, reboot your machine.

Please contact System76 support with any questions. When flashing firmware, it's better to be safe than sorry.

Thomas Aaron (tom-system76) wrote :

FREEDOS Image Attached

Thomas Aaron (tom-system76) wrote :

Firmware Files Attached

James Fisher (james-fisher27) wrote :

Applied the bios patch per instructions and noted that battery life has significantly increased and the fan properly throttles according to temperature.

Thomas Aaron (tom-system76) wrote :

Marking this bug fixed.

Changed in system76:
status: In Progress → Fix Released
mv (marxistvegan) wrote :

I am having trouble with getting FREEDOS to boot, I have a 2gig memory stick it installs correctly, but on bootup just shows FREEDOS in the top left with a cursor blinking. I let it sit for a couple of minutes but nothing happens.

Thomas Aaron (tom-system76) wrote :

We've seen this before. Typically, it is either a bad download of the bootable image or something peculiar with the flash drive. Can you re-download and try with a different drive?

mv (marxistvegan) wrote :

Thomas thanks for the reply, but unfortunately I am not able to successfully do this. I tried another usb but again it boots to "FREEDOS" and blinks without loading I changed to autoboot in usb by changing the boot order but again same thing. I am beginning to give up I'd love to have a better battery life, as it dies quite quickly under 1.5 hours on battery.

Thomas Aaron (tom-system76) wrote :

mv, I just duplicated the problem here in the shop. We think there is an issue with the Freedos image working on the larger flash drives. Do you have a smaller flash drive? 1GB or smaller?

Also, do you have an external DVD drive? If so, I can provide an alternate method of flashing the BIOS.

Thomas Aaron (tom-system76) wrote :

Almost forgot, what BIOS version do you currently have? The following command will tell you...

sudo dmidecode -s bios-version

mv (marxistvegan) wrote :

Thomas sorry for the lateness i thought I turned email notifications on this is what I get from that command

Alan Aversa (aversa) wrote :

Also, after doing the update, I still have BIOS version CALPELLACRB.86C.0000.X.0000000000, with the fan problem and all… Perhaps it didn't actually flash my BIOS? Thanks

Alan Aversa (aversa) wrote :

Could you please post a newer version of the ECS31000.2SA image file corresponding to a newer BIOS? Thanks

M4rotku (m4rotku-aol) wrote :

Has there been any update in the FreeDOS software that would allow for using a larger flash drive? If not, then how would I go about putting it on rewritable dvd?

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