Never really knew how hotswapping had to be implemented in a windows-system. Now i have found out.
Its AHCI which must be enabled in BIOS/Cmos-Setup plus Sata-driver must be installed.
A) New windows-installation
One must startup with MOBO-CD inside and boot from it. then(at least for asrock alive-dual esata2) this message will ask you to mount a floppy disk: generate serial ata driver.
Start system with AHCI activated in BIOS and booting from windows-CD/DVD.
Pressing F6 during start to install AHCI-Sata2-driver-
B) If system is already working, full driver-setup-program will install sata2-driver. There will be no more system-hang when AHCI is enabled.
One can then hotswap drives(removing and attaching) during PC-work. I am using flat orico 8512-series dockingstation(esata with usb-3.0 option).
This nonknowledge has created big problems on my external drive with partition table mixed up. see other thread.