Q:

Supporting 1680 x 1050 resolution under Microsoft Virtual PC 2007

We're running Windows Vista Enterprise as a guest OS under Microsoft Virtual PC 2007 SP1 (6.0.192.0) (running on Windows XP Professional host).  Our development workstations have multiple monitors, including a widescreen that supports 1680 x 1050.  The developers like to run the guest OS in full screen by using the right alt-enter feature and be able to maximize the screen real estate.
However, when I go to Control Panel > Personalization > Display Settings to change my resolution, I don't have 1680 x 1050 as an option: it goes from 1600 x 1024 to 1600 x 1200.  The monitor is reported as "(Default Monitor) on VM Additions S3 Trio32/64", which matches the emulated video card from Virtual PC.  The 1600 x 1024 setting leaves an area of the screen unused.
I think I could edit C:\Windows\inf\monitor.inf to add the new resolution, probably under the [Generic.NTx86] (Monitor\Default_Monitor is the hardware device ID for legacy descriptor-less monitors.).  However, I'm not sure exactly what to change.  Switching  from Virtual PC to VMWare Workstation or another product is not an option.

A:

This is not possible due to the limits of the virtualized video card that virtual PC virtualizes.
one workaround that I have seen mentioned but never tried was to boot up your virtual PC and then remote desktop to that PC. seems cumbersome and resource wasteful to me though.

A:

I'm using Virtual PC 2007 SP1 (6.0.210.0) with an XP guest. Right-alt-enter successfully puts the VM into 1680x1050 full screen mode. It appears I got the update to 6.0.210.0 from a hotfix rollup package (KB958162):

The resolution is now extended to
  2048x1920 (32bit). Virtual PC 2007 SP1
  supported a screen resolution of up to
  1600 x 1200.

Note that KB958162 also includes a new version of Virtual Machine Additions.
1680x1050 is also available in the guest's Display control panel, but selecting it causes a dialog (in the guest) that says "The display control panel is unable to change the display settings. You must have the appropriate administrative rights to change these settings." After that, 1680x1050 is no longer available. 

A:

Today I had luck and it went full screen.  When I checked Control Panel > Personalization > Display Settings, it was set at 640 x 480, which is the low point on the slider.  I think it has to due with the Virtual PC Console Settings > Display where "Virtual machine window resizing options" is set to "Allow any screen resolution."

