Hi, I have trawled google on this and can't find anything (difficult one to search for). But I have just switched my boot / Mountain Lion installation to an SSD external firewire 800 drive. With just that attached to the Firewire port, everything is peachy, boots really fast and everything in OS is great. However, if I also have one or both of my WD My Book firewire drives diasy chained, then the SSD struggles to boot. It's very slow, and after about 15 minutes, the logon screen finally appears, and then it takes ages after typing in my password. After that, once in OS, then everything is fine again. I have been disconnecting the 2 WD drives whilst booting and then re-connecting after boot, but that is a pain. So, I just wondered if anyone had any thoughts on what is causing this? Thanks.