Q: Exactly how much GPU memory is allocated to a virtual machine (VM) based on the number of monitors and resolution set?

A: I found the following values by looking at VRAM for the initial Windows Server 2008 R2 SP1 release of RemoteFX. I checked the available MB per GPU before a VM was started, then I set the VM to a certain resolution then checked the available memory again. Below are some screenshots I took while working.

Note that with three monitors, the maximum resolution is 1600 by 1200 and with four monitors, the maximum is 1280 by 1024. You can see rght away that having three monitors at 1600x1200 reserves the most GPU memory, 330MB. The other values are shown below.