Motherboard Code???

[Thundergy]

Hello. I built my PC may of 2015, and its been running fine for half a year with code 00 (Not Used) on the motherboard.

here is my computer: https://pcpartpicker.com/b/3PWXsY

4 days ago I ALT-Tabbed from a game, and when tried to reopen it, I couldn't get back into the game (black screen even when i launch it after pc restart)
I completely restarted pc (turned off PSU) and booted PC. Now my resolution got messed up 600x800 or something, and cant switch it back. In device manager under my videocard says Error Code 43

I flashed bios (Download bios from asus webisite, use renamer tool to rename bios to M7H (for maximus hero 7), put the file on formated flash drive, put flash drive under bios flash button, hold button until it starts blinking, wait for stop blinkin)

Now i cant boot into windows. (After windows logo loading screen i get a black screen with blinking cursor on top left corner)

I can boot into safemode and Mother Board displays a A0 code, which people say is fine. So wtf was the 00 code i ran my pc with for half a year??

Also for some programs it says my pc doesn't meet requirements for install. (When i tried updating i7 4790k intel HD drivers, i got same error message) if this is at all relevant.

[Journeyman]

With the Q-Code 00, I've never had VGA....

Were any of the LED's, close to the 24 pin connector, lighted?

[Thundergy]

Damn Iv'e never noticed any led flash or blink when pc used to work. Right now, with my pc problem (wont boot past black screen with flashing cursor) no LEDs are blinking. and i keep getting A0 code when im in safemode or if im stuck on that black screen with flashing cursor.

[Nate152]

Hello Thundergy

If your pc was working with code 00 I suspect you were using the 5 way optimization.

Try clearing the cmos with the button on the I/O panel then try booting. If that doesn't help and you have the windows dvd, insert it and boot from it and select the repair option.

If that doesn't work then a complete reinstall of windows should get you going.