Windows NT Hangs with Adaptec 2940 Enable Disconnect Set to No

• Microsoft Windows NT Server version 4.0
• Microsoft Windows NT Workstation version 4.0

SYMPTOMS

When you start your computer, Windows NT 4.0 may stop responding (hang) at the blue startup screen displaying the system processor and memory configuration. When this occurs, no dots appear on the screen, and you receive no error message. In addition, if you attempt to install Windows NT 4.0 from the 3 floppy diskettes your system may hang on disk 3 while displaying "loading SCSI floppy driver".

CAUSE

This behavior can occur if the Enable Disconnect setting is set to No in the SCSI configuration for the Adaptec 2940 SCSI controller in your computer.

RESOLUTION

Set the Adaptec SCSI controller back to the default settings. To do so, follow these steps:

1. Restart your computer. When the BIOS message for the Adaptec SCSI controller appears on the screen, press CTRL+A to enter the SCSI controller configuration tool.

2. Select SCSI Configuration from the menu.

3. Press F6 to load the default settings.

4. If the boot drive is not SCSI ID 0, go to the SCSI Boot Configuration menu under Additional Options and set the ID to match the drive that is the boot drive.

5. Restart the computer.

MORE INFORMATION

The Adaptec documentation recommends setting the Enable Disconnect setting to No if there is only one drive on the bus to improve performance. The Aic78xx.sys driver requires this setting to be set to Yes.