here are my specs: 256 mb of ram, intel pentium 4 2.0 ghz, radeon 9200 SE 128mb, and i'm not sure about my motherboard (it;s intel). On my mother board there are two ram cards and two other cards which i dont know what they are (they are next to the ram cards). Can someone please explain what the hell is "ddr", "SDRAM", "ddr2" ddr3" and "ddr400".