In order to boot your Atari as fast as possible, you can have HDDRIVER only check the device IDs that correspond to a potentially connected device. This way no time is lost during the boot process by trying to detect non-existing devices.
With "Devices and Partitions" you can configure the bus IDs, device IDs and LUNs to be checked in detail. But it is not required that you manually enable/disable IDs. Instead, simply use HDDRUTIL's "Auto Configuring" function. HDDRUTIL will run a device check and then open the "Devices and Partitions" dialog with all IDs found pre-selected. Usually it is sufficient to just confirm with "OK" in order to have HDDRIVER check only the IDs that really matter. Of course you can manually modify these settings any time.