No, you don't need to disconnect your HDD during an upgrade to Windows 10.
No, you don't need to disconnect your HDD during an upgrade to Windows 10.
Your setup doesn’t require disconnecting the HDD during the upgrade. You can upgrade Windows 10 from Windows 8.1 using your 250GB SSD and 1TB HDD without interrupting the drive connections.
I didn't do it, I'm just being lazy. Upgrading now, I'll let you know if I mess up.
I was considering the same idea... And then I noticed something unusual—"system reserved partition" was on the second HDD... not a partition, just a different physical drive. After that, during installation I removed all storage drives, which caused problems about once every 10,000 times, but they were real and it was simpler to disconnect the cables.
I did this for safety, just in case. Plus, since I triple boot and Windows 10 can mess with other boot loaders, I’m better safe than sorry. So I recommend unplugging them.