I've recently installed a dual boot setup on my PC, with XP and W7 running on seperate SATA HDDs. I have some boot-up issues that I can't seem to resolve. XP has boot priority in the BIOS, and so without my intervention the PC should boot straight to XP. XP is on the SATA 3 position on my mobo, and W7 is SATA 1. Symptoms as follows: Firstly, I never get the BIOS screen showing the 2 opertaing systems with the countdown timer, giving me the option to boot into one or the other. The only way I get to choose is if I hit F8 to manualy go into the boot loader and choose which OS to boot. Sometimes the BIOS cannot 'see' the XP drive or OS. This is evident in 2 ways -1) if I allow the PC to boot without choosing an OS, Ithe XP loading screen sometimes hangs for ages, and then reboots, and goes through it again. 2) if I go into the boot loader to choose the OS, sometimes it only shows the W7 drive. These problems disappear if I disconnect the W7 HDD. XP will boot normally and without problem. Plugging the W7 drive back in allows things to work properly for a couple of boots - I can see and choose both OSs - but then the XP drive will disappear again. I really want to be able to switch between the OSs without keep opening the case to disconnect the W7 drive. Any ideas? Cheers.