Hi there, My Specs: P4 @ 2.4Ghz 512 Ram @ 2100 80 Gigs Harddrive ATI Radeon All In WOnder 7500 64MB video card Asus P4S8X-MX Socket 478 --Motherboard I am in the process of upgrading my system by adding a new video card and a 512 Ram memory. The problem with my video card is that it doesn't play new games such as Age of Empires 3 and Ghost Recon 2. So I feel compelled to buy a new video card just to play those games. I am not going to spend more than $150 on video card alone. But there are so many freaking video cards out there that i'm almost confused as to which one to consider that would work best with m current system. Also there are so many new technologically equipped video cards out there that I hve no idea. If some one would care to explain what the following things mean breifly, I would really appreciate it. What is DDR on video cards? difference between DDR2 and DDR3? My motherboard Asus P4S8X-MX Socket 478 supports X400 video cards as says in the Bios-havn't a clue what that is??? whats the diff b/w X400 and X800 AGP? also what do these terms stand for? Would you suggest buying sealed pack video cards from E-Bay comp stores? There are some great deals for 9250, 9550,9600, and 9700, ATI-Radeon cards. Please share any good/bad experiences. last but not least, whats the difference between original video cards built by ATI RADEON and other ATI Radeon cards built by Sapphire, PowerColor, Gigabyte, etc.? Thanks a lot in advance.