Why can't the user display moving images or playback DVD video when user set refresh rate to 85Hz?

Why can't the user display moving images or playback DVD video when user set refresh rate to 85Hz?
or
Why do the following symptoms occur under the refresh rate of 85Hz?

--Symptoms--
1. [WinDVD], [MediaBarDVD], [SmartCapture] and [CyberCodefinder] that requires overlay function, do not boot.
2. The playback of moving images cannot be done smoothly either.



This symptom is due to the specification of the video chip (built in Intel 815EM chipset) used in this machine. The hardware overlay function does not work in the refresh rate of 85Hz, and cannot playback moving images. To use the hardware overlay function, user have to establish a refresh rate setting other than 85Hz.

Execute the following procedure to change the refresh rate setting, when user want to playback movies with connecting RGB external display. User need to have an external display with RGB connection .
* Settings to change the refresh rate to 60Hz

Please follow the procedures below:
1. Click Start, slect Settings and click Control Panel.
2. Double-click on the Display icon to display the Display Properties dialog box.
3. Click the Settings tab and click the Advanced button.
4. Click the Adapter button and select 60Hz from the pull-down menu of the Refresh box. Click OK.
5. Click the OK on the Display Properties dialog box to close it.

The hardware overlay function also doesn't work and moving images cannot be played back in the following environment:
- Virtual display
- 1280 x 1024 (SXGA) 24bit