Just out of curiosity I opened up Sonar and loaded several soft synths (Hybrid, TAL Elektro, Addictive Drums, and Cthulhu) as well as several plugins with graphic displays (Voxengo Span, CA-2A, LP-MB. Melda MOscilloscope, and Pancake2).
My baseline graphics properties looks like this (Intel HD Graphics 2500):
Using GPU-Z my graphics memory use looks like this while running Sonar:
So my dedicated video RAM is 32 MB, but while running Sonar, it seems to average below 200 MB. It looks like the graphics adapter could allocate up to 1.792 GB RAM, but that is unlikely just using a DAW.
So that still is not a very big chunk of my system memory... no worries!