The NetWinder 3100 is the successor to the original ARM-based version. It features a Transmeta Crusoe 5400 processor, an Ali 1535 southbridge, and three Realtek 8139C ethernet interfaces. There are two serial ports, a parallel port, and two USB ports, and a 2.5" IDE disk drive. An optional daughtercard adds a Type-II PCMCIA slot (this variant is called the 3300).

The 3x00 series was designed in the fall of 2000, and was just about ready for volume production when Rebel.com fell into receivership in mid 2001. Exact numbers are hard to get, but it is believed that about 100 units were built by Rebel. A significant number of these went out as evaluation units to magazines and potential customers, few of them ever returned.

Physically the 3x00 series uses the same plastic case as the original NetWinder did, but the colour was changed to grey with a dark blue base. Compared to the original ARM-based NetWinder, the Crusoe processor delivers about four times the performance, while actually consuming even less power. As with the older series, rackmount versions also exist.

The rights to the technology now rest with a company called NetWinder Inc. They continue to offer support for existing customers and are apparently planning to resume production of the 3x00 series. Their focus appears to be more on the OEM and embedded development than on an end-user product.