Download the HP LaserJet 6P/6MP printer driver for Windows NT 4.0.
FreeImage driver
FreePrinter driver
FreePrinter driver
FreeImprove performance with the DeskJet 400 PrintSmart driver.
FreePrinter driver
FreePrinter driver
FreePrinter driver
FreeGet this set of Windows 3.1/95/98 printer drivers from Hewlett-Packard.
FreeGet the LaserJet 5/5N/5M PostScript driver for Windows NT 3.51.
Free