Memory problems

I bought a 1g memory, but only after the show to use 512m, I would like to ask why this is? My motherboard is tm-vm800

some graphics cards have been taken away to the ~~~~~~~~! ! Do you sympathize with integrated graphics ah, do you allow the traders to Hu You.I think that the 512 had been cheated, really, do you buy is the 512, look for businesses to change than people cuttlefish for you! Mongolian old!