This has been a problem for months. They will work alone, but they won't chain. I tried using different cables, all ports. Originally both were Fat32 formatted, but in my efforts I formatted one of them to Mac OSX (one drive is better than none when using windows). Neither the FAT or the OSX can chain in tiger, no matter what order I put them in. The computer will only read the drive that is directly connected to the computer. Any advice? these are firewire, by the way!