No, my latest bios lists all the disks connected to the system and allows you to specify each individual disk in whatever order you like.
Obviously with USB, you can just say 'first usb device' but if it is actually connected, you can select which one to boot off.
Yours may well list them all.
For an example a PC that has a RAID data drive will typically insists on booting from the RAID drive rather than an SSD drive.
BIOS has no option or is over-ridden to attempt to boot from the RAID drive and we have to intervene to boot off the SSD.
You now know one of the reasons I have never bothered with MS supplied backup utilities... not least they have a habit of changing them for incompatible versions between one version of the OS and the next.
There's a free utility called Easy BCD which allows multiple OS including the one you set as default. No reason why you couldn't have two Win 7 - just give them a different name (Win7 and Win7A, or whatever)
Your reference to 'spinning rust' amuses me. The SATA drive I dismantled this morning to destroy the data had four platters that appeared to be coated in a nickel deposit, though probably somewhat more complex than just nickel - I well remember the 5 & 10 Mb 'exchangeable' disks on mini computers in the 1970's that had a ferric oxide coating on aluminium platters, and you knew if you'd had a head crash by the red dust when you opened the machine :)
Andrew
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