NT 3.51 Print Manager
The print manager allows you to add new printers, but it unfortunately does not seem to allow you to add network printers, even on the Workstation edition.

NT 3.51 Display Mode
Windows 3.1 had to rely on it's setup program to change video modes. Windows NT can change them on the fly.

NT 3.51 Networking
The control panel also contains a number of NT-specific options, such as this network configuration utility.

NT 3.51 Services
Windows NT also allows you to configure certain services to run manually or automatically on login.

NT 3.51 Shutdown
Shutting down NT 3.51.

Conclusion:
Windows NT 3.51 is not any different from NT 3.1, however like Windows 3.0 and 3.1, NT 3.51 was much more widely used from all appearances.

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