The basic configuration of my system is as follows:
CPU: Pentium G620
MB: GA-H67N-USB3-B3 (BIOS F6E)
RAM: A-DATA DDR3 1333 4G *2 (run at 1066 MHz)
OS: win7 sp1 64 bit
Video driver: 8.15.10.2462
Dynamic Energy Saver 2 version: B11.0325.1
The Intel integrated graphics is connected to a 19” LCD via HDMI port.
At first, the screen flickered and computer halted randomly, with all the BIOS settings kept as default. Through Google, I found people from all over the world are facing the same problem with this little board:
http://forums.tweaktown.com/gigabyte/44012-ga-h67n-usb3-b3-faulty.html ,
http://forums.overclockers.co.uk/showthread.php?t=18262069 ,
http://mbforum.gigabyte.de/index.php?page=Thread&threadID=3733 ,
http://www.chiphell.com/thread-185979-1-1.html . Thanks to their solution, I increased the graphics voltage a bit in the BIOS and it worked indeed.
However, when I turned on Dynamic Energy Saver (DES) the same display problem recurred immediately. Although I played with all the options in DES, as well as different settings of graphics voltage in BIOS (even set the graphics voltage to a high value of 1.355v), nothing helped at all. What I do found interesting is that, if the graphic core is running under a heavy load, the system works perfectly fine with DES on, but as soon as the graphic core goes idle the screen would flicker again.
I guess in my case the default graphic voltage set by BIOS is too low to work normally. To reduce power consumption in idle mode, the DES software further lowers the voltage and that overrides the manual voltage setting. It would be nice if this problem will be resolved in next official BIOS release of F6 .
