Hi,

In the event viewer we are seeing a warning for "The speed of Processor 3 in group 0 is being limited by system firmware" & "The speed of processor 2 in group 0 is being limited by system firmware.

We have just applied the October 2014 updates but are experiencing unexplained system restarts. Have read that this could be related to power options but the event is occuring from every restart, full battery charge and plugged into the powered dock. The system restarts occur randomly.

We are also experiencing a black screen at domain joined user logon which is only resolved by initiating the power button which then prompts to shutdown.

I shall suggest you to post your problem here:

http://answers.microsoft.com/en-us/surface/forum/surfpro3?tab=Threads

Hi,

After researching for a while, I noticed that this issue is related to Intel(R) SpeedStep Technology.

Please check following steps to check your issue:

Disable Intel(R) SpeedStep Technology
http://www.intel.com/cd/channel/reseller/asmo-na/eng/203838.htm

Also, I suggest you update firmware to the latest version.
Surface Pro update history
https://www.microsoft.com/surface/en-hk/support/install-update-activate/pro-update-history

Thanks for your response, will test.

Intel speed step doesn't appear to be installed on an option in the UEFI.

Intel speed step doesn't appear to be installed on an option in the UEFI.

Intel speed step doesn't appear to be installed on an option in the UEFI.

Hi,

We can only help you on system side, for further help, you may need to contact the manufacturer or Surface support as S.Sengupta mentioned.

http://answers.microsoft.com/en-us/surface/forum/surfpro3?tab=Threads

Thanks for your understanding.