Dynamic video memory technology (DVMT) allows dynamic allocation of system memory for use as video memory to ensure the most efficient use of available resources for maximum 2D/3D graphics performance.
How it works
The amount of video memory is dependent upon the amount of pre-allocated memory set for your system plus something called DVMT. DVMT, as its name implies, dynamically allocates system memory for use as video memory to ensure the most efficient use of available resources for maximum 2D/3D graphics performance.
It is a technology used by Intel to fulfill the needs of graphically demanding games.
References
Dynamic video memory technology Wikipedia(Text) CC BY-SA