I've tried a few Linux distros on a range of older laptops which have Windows 10 installed on them. Linux was installed as a dual boot on a separate partition to Windows. After installing Linux, Windows would boot normally in around about the same time as it did before partitioning however, the Linux distro (Ubuntu, Debian, Manjaro and Linux Mint) would boot really slowly and I've noticed long periods of no hard drive activity during this time. After long gaps of no hard drive activity the OS would boot to the to the desktop. But it would take at least 3x longer then Windows 10 cold booting.
I'm not sure if this is just a problem affecting me or is this a problem with dual booted Linux.