If your mobo doesn't support DMA 100, the Promise Ultra 100 and an 80 wire cable won't help. I'd still get the DMA 100 for when you upgrade to a system that does support it. The price difference is kind of insignificant, so I'd say go ahead and get the drive you want. I want to add a bigger hard drive to my system. On reading my motherboard manual I see it has an Asus P2B motherboard with Ultra DMA/33 bus master IDE. My hard drive is Fujitsu 6GB. What I would like to know is can I get any benefit from a new ultra DMA 100 7200 RPM drive and make it the master? Do I need a Promise Ultra 100 and the 80 wire cable for this? PCBUILD maintains hundreds of useful files for download visit our download web page at: http://freepctech.com/downloads.shtml