In that second thread on the MS forum, suggestions include looking at the "msinfo32.exe" output as well as "control panel...display...screen resolution...advanced settings... adapter". On my machine, the results are contradictory.
Msinfo32.exe reports exactly 1 GB of video RAM (actually 1,073,741,824 bytes).
The Control Panel sub-menu reports as follows:
Total Available Graphics Memory: 4859 MB
Dedicated Video Memory: 3072 MB
System Video Memory: 0 MB
Shared System Memory: 1787 MB
And meanwhile, DxDiag reports this:
Display Memory: 734 MB
Dedicated Memory: 3043 MB
Shared Memory: 1787 MB
I'm really getting to hate nasty old Billgatus Of Borg.