My actual problem is that in a multiple monitor set-up, my second monitor is more than 4 years old, and its maximum (and optimal) display resolution is: 1680 x 1050. Windows 8 itself detects this size properly, albeit it spits out a small warning on the "Screen Resolution" panel:
Your resolution is lower than 1536 x 1080. Some items might not fit on your screen.
I also use VirtualBox, and I use the "Fullscreen" feature (available with Guest Additions) to get the virtual machine to use the entire display. However, Windows is somehow fooling VirtualBox into thinking the display actually has the resolution 2520 x 1575. This causes images and text in the VM screen to be smaller than I am accustomed to (when using the same setup with Windows 7). Some text sizes that were previously fairly easily readable is now almost unreadable.
The scaling mechanism is fairly sophisticated, there is anti-aliasing going on and all that, but I would just rather that Windows leave the display size in its native size.
How can I tell Windows 8 to leave the display size alone?