[SOLVED] second monitor only works when mirroring first monitor

[DamoG1]

so after coming back home during the holidays my computer failed to boot up, and kept on showing the logo for rog. after like 5 cycles of this windows says that it couldn’t start up and i’m at the troubleshooting menu. i tried every option available short of resetting my computer. what i found out was safe mode worked but only on one monitor. so i have no idea what to do and go back to booting up normally. i manage to get to the login screen but everything on my left (main) monitor is fuzzy and i see lines of stuff on my taskbar all over my screen. my right screen is always black during login so i think that’s why it looked like it didn’t work beforehand. now that i’m in my right (secondary) monitor works fine but my left one is still fuzzy and lags 10s behind my input. so i mess with the settings and find out that my left monitor works perfectly (albeit at a lower refresh rate) when i mirror my right monitor on both of them. also i want to mention that the fuzzy lines show up when i restart my left monitor so somehow windows hacked my monitors and i have no idea what to do from here. sorry for the long post but i want to include all the details

 

[lordmogul]

What connections are the screens using (VGA, DVI, HDMI, DisplayPort, etc) and what GPU are they connected to?
Are the graphics drivers installed?
Are the monitors detected correctly? (Both in the graphics driver menu and Windows device manager)
Are both set to a resolution they can display? (Optimally the native resolution on flatscreens)

Only having a picture on a single monitor during boot and login isn't to uncommon.
My 1060 for example goes by order DP -> HDMI -> DVI and displays that stuff on the first port in that order.
On my old 660 Ti it goes HDMI- > DVI 1 -> DVI 2, with the same thing.
My old HD 4870 and 8800 GT from days past did display the boot on both DVI ports, so ymmv.

Safe mode runs on single display by default. It's safe mode after all, so the less is running the less can cause issues.

If everything is connected correctly, try "uninstalling" the monitors in device manager and do a restart, then Windows should detect them again on next boot. Another thing to try is to boot with only one monitor connected and plugging in the other one later.
Yet another step would be to uninstall the graphics driver, check that Windows is fine with them like that, and then install the driver again.

 

[DamoG1]

i tried the device manager method and it worked thank you so much