Also:
Highly recommend you increase your Ram to 4 Gigs.
1) You did not indicate which OS you have ie 32 bit or 64 Bit. If 32 Bit then 4 gigs is the max you can use, with 64 bit typically the Max is 16 gigs which is the limit imposed by Windows 7 Premium (Higer versions allow more than 16 gigs).
2) You did not indicate what ram you have, ie is it Two x 1 Gig sticks or is it One 2 gig Module. If only one module then you are running single channel, NOT the recommended daul channel mode.
.. If you have one 2 gig memory module then you can simply buy 1 IDENTICAL 2 gig Memory module. If two 1 gig modules then you could add two additional 1 x 1 gig modules. Alternately rather than 4 x 1 gig modules you could buy 2 x 2 gig modules.
$ gigs (2 x 2), Approx $40:
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007611%20600006127%20600006066%20600000261%20600006157&IsNodeId=1&name=9
2 gigs:
1 x 2: aprox $20 -
http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=100007611%20600006127%20600006061&IsNodeId=1&name=2GB
2 x 1 (LIMITED Choices from Nwegg):
http://www.newegg.com/Product/Product.aspx?Item=N82E16820231185&IsVirtualParent=1
NOTE Also if adding to your existing Ram needto look at speed. The Default spped for your CPU is DDR3-1600. The Modules I have listed are all DDR3-1600. Sof if your existing ram is DDR3-1333 and you opt to add, not replace then you should stick with the DDR3-1333.
DON'T know, then download/install, then Run CPUID CPU-Z and look a the Memory tab - that will tell you HOW the memory is being used (SPeed/Timing/an single or daul channel). The SPD tab will identify manuf, speeds and timings that are stored in the memory. NOTE also verify voltage, should be 1.5V ram. Low voltage ram (ie 1.35V ram) will void the warranty for your CPU as will 1.65 Volt ram.
Link to CPU Z: http://www.cpuid.com/softwares/cpu-z.html