Question Power and display error

[Kahandral]

My motherboard does a POST beep code for virtual mode exception error (7). Because of this I get no display. But if I use a graphics card everything works fine. But another issues it seems that the motherboard is going into a weird hibernation mode when asked to shut down. The computer does shut down the LEDs go off and the display goers off but the fans inside are spinning so its like it went to sleep instead of switching off. Any ideas what may connect these two problems? I already cleaned the motherboard and reset the BIOS.

 

[rgd1101]

full system spec? include make and model of the psu
what os?

 

[Kahandral]

Its a win 10

Intel Core i5-750

The power supply is a Bestec ATX0350P5WC 300 W

8 GB DDR 3

ATI FireMV 2260 (256 MB)

The motherboard itself I'm not sure cos the problem has escalated now that the PC powers itself off before I get a chance to check the system information I know that it is not the original motherboard. This motherboard is unbranded as well.

All parts have been tested the power supply, RAM, HDD, processor and GPU is working.

Also worth noting that whether the PC receives power even if no power button was pressed it automatically goes to sleep mode.