The stock CLP-620ND driver works only in monochrome. All color printing just hums for a while and outputs nothing.
To get everything working in color I installed it as a CLP-660ND printer. The installation did not go smoothly as it refused to accept the plxcolor driver. But when I first installed the printer chosing the PostScript driver and after that installed it with the plxcolor driver everything works nicely.
The printer still reports a paper jam all the time. But it does not affect operations.
Make and Model:
Samsung CLP-660ND Foomatic/pxlcolor (recommended)
Hope this helps