I have an Intel DQ77KB with an i7-3770T, an Intel WiFi Card (half size), a SSD (SATA 3) connected with an external HP 90W power supply running Ubuntu 12.10. The monitor (27", 2560x1440) is connected via Disyplayport. I had to disable the embedded Displayport (eDP) in BIOS, otherwise Ubuntu sees two connected displays
The motherboard makes an high pitch sound which is really annoying. I found a solution to get rid of the high noise. If I put a header pin on the Panel_Off header, the motherboard gets completely quiet. But simultaniously a process (kworker/0:1) takes 100% of one CPU (exactly about 95%).
So my question: What is the header Panel_Off for? In the description it just says Monitor_off.