Shop for a gtx 750ti.
That should be a straight swap and give a nice bump in gaming perf.
It is not 4GB.
If you try to move above that to some 4GB card expect to upgrade the psu.
450w is not going to cut it.
It's your budget and your call.
I have an Avatar FX6164. I love it, but I need to upgrade for some games that I play. The specs are great, but I just want to upgrade to a 4gb graphics card. Got any suggestions on a card?
Here's the link for the desktop:
http://m.newegg.com/Product/index?itemnumber=N82E16883258020
Thanks in advance!

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