my Geforce GTX 750 ti 2GB graphics card states that there is a total available graphics memeory of 4096 MB but the card is only using 2048 MB, of course my edition is only 2048 MB of vRAM but why is there 4GBs of potential graphics memeory not used? I do not understand why I cannot use this extra 2GB for my gaming, considering the newest games require more than 2048 MB of vRAM, can someone shed any light on this and if there is a way of using this extra RAM