The 65XE has 64 KB of RAM and is functionally equal to the 800XL minus the PBI connection. The 130XE has 128 KB of memory, accessible via bank select. The 130XE was intended to appeal to the mass market.
The 130XE has added the Enhanced Cartridge Interface (ECI), which is nearly compatible with the Parallel Bus Interface (PBI), but smaller physically as it sits next to the standard 400/800 compliant cartridge interface. It provides only those signals that did not exist in the latter. ECI peripherals were expected to be connected to both the standard Cartridge interface and the ECI port. Later revisions of the 65XE also include the ECI port.
The 65XE was marketed as the 800XE in Germany and Czechoslovakia to capitalize on the popularity of the 800XL. All 800XE units include the ECI port