well, one is a Toshiba 120GB DMA5 and one was a WD 120GB DMA6. I was going to install an SSD for the OS and keep the 120GB as the apps but thought I would dabble in the RAID first. I just wasnt sure you had to format the array as striped? Seems the Fasttrack builds a mirror all by itself as you can do that with a working drive, but not a striped. you have to start from scratch, and 2 120's made 1 240GB drive array. I thought for all this time that it would stay a 120, but it would be like 2 identical drives sending the info twice as fast, like 2 heads reading instead of one. Oh well, Im not out a PC I got 4 more laptops to fall back on, this one is just the biggest/baddest- fastest. In 2006 it was the fastest laptop on the planet...! Of course its not nowadays...but its like having a Hemi Cuda, fastest at one time but not any more.