I have W7 loaded on a SATA HDD using Native IDE in the BIOS. It is using IDE Channel 2 Master I plugged in another SATA HDD, one that has WHS2011 installed on it, so it also has a boot partition, but it is the slave. It is using IDE Channel 2 Slave I'm confused though, why does the slave WHS2011 boot over my W7 boot HDD? Also my W7 has the hidden Boot folder, and holds the boot configuration data store, if that holds any merit in this. I'm really puzzled over this, but I do admit, I really don't understand how the HDD priorities are determined, especially in this specific scenario . Does it have something to do with that 100 MB hidden partition on the WHS2011 drive? I just noticed, it has that, and my W7 doesn't. How can I add that to my W7 drive? Thanks I attached my disk management screen shots.