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disk operation are set to start correctly. On a system running Windows NT Workstation 4.0,
the Atdisk device and the Pcmcia device should be set to start as System devices.
Do this before inserting a PC Card hard disk device in the PC Card drive. If you do not,
anomalous behavior may result -- for example, the PC Card hard disk drive may not be
detected by Windows NT Workstation, or may be detected as the system drive (drive C).
To change startup type for device drivers that control PC Card hard disks:
1. Open Devices in the Windows NT Control Panel. The Devices dialog displays.
2. Highlight the device in the Device list; then select Startup. The Device dialog displays.
3. Under Startup Type, select the appropriate startup type; then select OK.
4. In the Devices dialog, select Close.
Disable Command Queuing
To improve standalone system performance and to improve performance with some high-
performance SCSI peripherals, you should disable command queuing in the Windows NT
Registry.
WARNING
Do not change values in the Registry other than as directed. If you introduce incorrect
values into the Registry, you may cause serious operating system problems, and you
may have to reinstall the operating system. If you change values in the Registry that
make your system unusable, you may be able to restart the system and use the Last
Known Good Configuration option to undo the damage. Refer to the operating system
documentation for more information on the Last Known Good Configuration option.
To disable command queuing:
1. Start the Registry Editor (regedt32.exe) to open the Registry.
2. Open the following subkey in the Registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\aic78xx
3. From the Edit menu, select Add Key.
4. Type
Device into the Key Name box, and then select OK. Do not set a Class value.
5. Open the following subkey in the Registry:
HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\aic78xx\
Device
6. From the Edit menu, select Add Value.
7. Type
DisableTaggedQueuing into the Value Name box.
