The algorithm that Windows uses to allocate drive letters is bizarre.
Something like...
The first primary partitions on the master drives on the two IDE slots are given C and D.
Then the secondary drives, first primary partitions get E and F.
Then, the other primary partitions and logical partitions, in a similar pattern, one drive at a time.
Now, I can't remember whether it takes any note of which partition is marked bootable.
I can't recall if CD/DVD drives come in the middle or at the end.
Anyway, once you have an installed system, you can change the drive letters around.
That will be totally ignored when you re-install.
Also, all bets are off if you have SATA/USB drives in there. I've no idea where it puts those.
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