A very important aspect of your question is contingent on which operating system you are using. If you are using Windows XP 32bit then you are perfectly fine with 2GB!!! If you run any kind of 64bit OS then you should have 4GB (ideally 8GB) of memory installed. As for the 800 ram, that is perfect! Save your cash, and don't buy into the 1066mhz marketing trick.
------------------------------AMD Phenom II X4 940BE @ 3.63Ghz | MSI K9N2-SLI Platinum | BFG GeForce GTX 275 OC | 8GB G.Skill DDR2-1000 4x2GB 4-4-4-12 | Corsair 650TX psu | Sound Blaster X-Fi XtremeGamer| 3TB SATA | Windows 7 Professional x64
Reply to omnimodis78
If you are using a 64bit OS then yes, go to 4GB minimum. Don't worry too much about the speed of your memory. If you're using a 32bit OS then just stick with the 2GB RAM you have; increasing the memory in this case won't hurt but it will also not help - it would just be a waste of your money. Going from 800 to 1066 will not yield higher framerates, faster loads, etc. Off topic, don't stress out over 3d Mark points - you have a good system, just enjoy it!