Schematic for Likom Monitor, Model : L4032ND

Hi, I have a Likom 15" monitor (Model : L4032ND). Working fine in VGA mode (640 x 480 resolution). When switching to SVGA mode (800 x 600) the display just cut off & the LED on the monitor start blinking. When switch back to VGA mode, the display return & working fine. Appreciate if anyone can send me the schematic diagram & some tips on this.

Thank you in advance.

Best Regards,
Simon.