Aurora R9, ran Updates, not connecting to monitors

< it doesn't connect to any monitors.

What makes you think it is even BIOS-Posting and booting at all?

Sounds like a BIOS update might have been forced upon your Aurora-R9, and it went badly.

... so how do I fix that?

If you really can't find the "Failed BIOS Upgrade" troubleshooting steps, just let us know.

However, that would be strange since about 40% of the messages on this forum are related to that.

I've read the BIOS Recovery page, but it's not powering my keyboard so I can't use CTRL+ESC.

edit: also, after that, how would I go through selection menus without being able to see them?

Did you try a CMOS reset?

CMOS reset 

Item 12 on that picture.

CMOS Clear instructions 

Let us know if that made any difference or not.

hello!

I did that,, and now my computer is in an endless loop of restarting. 

First, it boots up, and immediately bluescreens, saying that there's an error. Second, it goes into supportassist, and does a system scan. It says "no hardware issues found" and goes into OS Recovery. Third, It says there's an OS_BOOT_FAILURE, and tries to repair. it only finds an error with the Partition Table, says "We've restored your PC to a working state", and restarts. Then it repeats. 

now it's restarting over and over with a DRIVER_VERIFIER_DMA_VIOLATION

Windows 10 is busted.  try a fresh clean install of Win 10 now you have got video on screen, using a bootable USB installation media (MS media creation tool).  After successful Win 10 Pro install try to edit group policy to disable automatic Windows 10 update.

Yes, your Windows installation seems to have issues. At least you have your monitor working again.

I've done this, but it's still 

boots up -> blue screen ("DRIVER_VERIFIER_DMA_VIOLATION") -> restarts -> repeat

how do I get to command prompt? there's no menus or anything I can select. 

I would do a reinstall with a bootable Windows USB media. Looks to me like your windows installation is corrupt, Hopefully you have a recent backup of your important data.