If I'm not mistaken....
Virtual Memory = Hard Drive
Physical Memory = RAM
...so the problem is with your RAM.
...I *guess* it could be the RAM that's on your video card, too, but I've seen errors for when that happens and it doesn't use the term "Physical Memory"...
I'm going to assume that since you don't know what kind of video card you have you didn't build this computer yourself, and it's a name brand (Dell, Compaq, HP, etc.). Not to insult you if you did, but if you bought your computer from one of those companies, I'm going to assume your knowledge of what's in the PC is very limited.
If true, here's what you can to do: somewhere on your computer's case (not the monitor) there's a model number or serial number, or some type of unique ID that you can search for either with Google or on the website of the company that build the computer.
Let's see what kind of RAM you've got & how much.
Also, is the GeForce card in your computer the one that came with it, or did you have an upgraded one installed?