Black Screen of Death, can't even access Windows, need help

Apologies if this is in the wrong forum section, wasn't sure where to put it. Anyhoo:

Having trouble with the black screen of death. Desktop is brand new, booted up just fine the first time, no issues. Restarted it to allow updates to be applied, then nothing.

After looking through tons of youtube videos and help threads I am stuck.

All I get is a black screen with a mouse cursor (that I can move, for all the good it does me)

I've tried every possible key combination out there, nothing works. F8, F12, Ctrl-Alt-Del, nothing. Can't go into Safe Mode, can't access the BIOS. All I get is the Windows opening chime and a black screen where I would normally log in to access my computer. Every connection is secure, nothing loose.

Can anyone help?

Using Windows 7 as the OS.