When configuring printers in NetWare Services, the default is polled mode. Polled mode, while theoretically not as fast as interrupt mode, still sends data faster that most printers can process it.
The advantage of polled mode is that it eliminates any possibility for interrupt conflicts with different hardware configurations. However, on complex printing setups with multiple printers running off a single workstation, polled mode may noticeably slow the execution of other tasks running on that workstation.
On a workstation that is running only NPRINTER with no other operations assigned to it, interrupt mode should be faster than polled mode.
On a non-dedicated workstation, polled mode usually provides the best performance.