I have 4 x HDDs on SATA AHCI (Intel Controller) in Native Mode and 1 x ESATA on Win 7 Pro X64. I noted that looking in Admin. Tools\Computer Management\Storage (as an example) the 1st HDD (Port 0 in the AHCI BIOS) is showing as "Disk 2" instead of my expectation of "Disk 1". Selecting the Drive's Properties correctly shows the "Location 0 (Channel 0, Target 0, Lun 0)". I also note that the Disk Number allocation in Windows will change randomly after some reboots/startups - going anywhere from "Disk 1" to "Disk 4". I can force/replicate this behaviour by removing the ESATA drive. Is this expected behaviour? It doesn't appear to create any operating issues at this stage, however, is there a way I can force the Drive to always map to (eg) Device 0 --> Disk 1, Device 1 --> Disk 2, etc? Thanks.

Hi, As far as I know, how the disk is plugged physically and the order it is displayed are not related. For a simple example, if a drive is plugged to SATA interface 4 and it is the only disk, it will be displayed as Disk 0. If there is no related issue about the disk order, I think we can safely ignore this. Meanwhile, I would like to share the following information with you for your reference: Master boot record - Disk identity Please Note: Since the website is not hosted by Microsoft, the link may change without notice. Microsoft does not guarantee the accuracy of this information. Hope this helps. Thanks. Nicholas Li - MSFT Please remember to click Mark as Answer on the post that helps you, and to click Unmark as Answer if a marked post does not actually answer your question. This can be beneficial to other community members reading the thread.