ddr is faster than sdram, older systems run pc100-133 sdram, if you can "steal" a pc133 system, say ($200) 1ghtz or better "socket system, (not slot) they'll do most any work a ddr system will, given the cpu speed is high enough, 2ghtz upgradeable, just a little slower, but, there usually not as upgradeable possibly leaving them inadquate in that field...