After booting my Lenovo Thinkpad E540 with an external monitor connected, one core is 50% busy with Deferred Procedure Calls (DPC) and it runs constantly at 100% clock speed (2.2 GHz).
After unplugging / reconnecting the HDMI cable, the system load goes down to almost 0% and the clock to about 40 %, as it should.
xperf revealed, that the Intel Management Engine Interface produces the load (Driver: HECIx64.sys, Version 9.0.0.01287 from Intel Dec. 17th, 2012).
After disabling the "Intel Management Engine Interface" AS WELL AS "Intel 8 Series / C220 Series USB EHCI #2 - 8C2D" in the Device Manager the DPC-load goes down close to zero.
Are there any real solutions ?
How to reproduce the high load:
(1) The Monitor is connected via HDMI, then power on the Thinkpad while shortly opening the Thinkpad.
(2) After logging in, the Task Manager shows 50% load at one core, the Ressource Monitor shows that all the load is consumed by Deferred Procedure Calls and that the clock is constantly at 100 %.
(3) Open the Thinkpad and disconnect the HDMI cable. The load goes down to almost zero and the clock below 50%, as it should be.
(4) Reconnect the HDMI cable and the load stays at almost zero.
Some Details:
Thinkpad E540, i7-4702MQ, 8 GB, screen resolution 1920 x 1080
Monitor HP LP2275w, resolution 1680 x 1050
Win7 64bit SP1, up to date by Windows and ThinkVantage systemupdate
The intel IGP is active (not Geforce 740M).
It does _not_ matter if only the external screen is activated or the internal and externale are expanded or duplicated in the display settings of Windows.
Thank you for your help.