Computer suggested a higher resolution, now the login screen is unusable?

[Necrodomis]

Let me elaborate:

 

PC says YOU CAN HAS BETTER RES!

I said OK!

Now I cannot see the login screen to login, and cannot click on "settings" at the main login screen. Splash screen during load is ALSO massively displaced, so I am not 110% on how to fix the resolution back to something that I can use easily. Is there a config file I can look into and change the resolution via some form of backdoor?

[Silk]

Look at link down in my siggy.