HP Deskjet 820cxi Printer
The HP DeskJet 820C Series Driver Version 8.5 supports Windows NT 4.0. This new driver has many driver fixes over the previous 8.2 driver.
Save the .exe file for your operating system to your hard drive, and double-click on it. This will expand the files and start the driver installation process automatically. Minimum system requirements for Windows NT 4.0 is 486 66 MHz with 16 MB of RAM.