Adn even if it could allocate 2 GB it would still be your system RAM.
Even with DDR4-3200 you will sit with a bandwith of around 48 GB/s
As comparison a GTX 650 has around 80 GB/s, a GTX 750 Ti around 86 GB/s, a R7 260 has around 96 GB/s, the GTX 1050 and RX 460 have arond 112 GB/s, a RX 480...