PC allocating ram to GPU?

I looked at my DirectX Diag tool and it showed me this:
The video card is supposed to only have 1GB of memory, and I noticed this number went up when I added another stick of ram to my PC.system specs:
Dell Dimension 5150
Windows 7 Ultimate
Pentium 4 2.8GHZ HT enabled
2GB DDR2 Ram
Nvidia Geforce 210 1GB(don't bother telling me to upgrade to a new PC, I know this one isn't top of the line but I can't afford one right now)

its a feature called turbocache I believe, it uses some system ram as texture memory, similar to how AGP cards did (back then it was called AGP aperture). The card itself only has 1GB onboard.Also it could be that dxdiag is quite simply wrong, it shows my card as having 758MB ram.

So will it use the extra memory when it has to, or will it use it all the time?

only when needed I imagine.

Ok, I've looked up turbocaching, and there's no way to stop it on windows 7... I'll live with it then