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То есть, на Disk 0, который был в BIOS помечен как Master, поэтому раздел System Reserved и создался на нем.

SATA drives numbering is decided by the position in ports. However You can change the order shown by Disk Management by installing a new OS to a different drive. When using SATA drives Windows decides Masters and Slaves by your Bios boot order. The first Drive with a Windows OS will be listed as C: and as Disk 0 In Disk Management. So If you install a new drive and put it in place of the other drive (Disk 0) you need to check your bios and make sure it is the first Hard Drive in the boot order if you want it to show as Disk 0 in Disk Management. It is ok to have other devices before it but must be the first hard drive. Also you must check your motherboard documentation. Some manufacturers actually make specific ports master or slave.

Windows often places a 100Mb (в вашем случае 500 Mb) System partition at the beginning of Disk 0 though

Why You Should Always Install Windows on Disk Zero