I've got 2 SSDs (1 M2, 1 sata) and three mechanical drives. The mechanical drives are used for data only (no applications at all) and it's not read often, so they're set to spin down after five minutes of inactivity. However I can hear them all regualrly spin up again (often at the same time), around 1-10 minutes after they power down. They're by far the loudest part of my PC and it drives me nuts.
Page file is not on a mechanical drive, no OS files, no applications, no services, search indexing is off, checking process monitor and no writes are occurring to those drives.
Why is it happening? Make it stop happening please.