 Will Cat5e do Gigabit Ethernet speeds? Cat5e has a maximum capability of 1 gigabit Ethernet. The older standard of standard Cat5 had a limit of 100 megabits transmission. However, this category of cable is not manufactured anymore. In addition, it is rarely seen in old installations. In rare cases, older phone systems may be wired in standard Cat5 and would not be suitable for Gigabit Ethernet. Can Cat5e support 10 gigabit Ethernet? Cat5e is not specified or recommended for 10 gigabit Ethernet. Therefore Cat6a is the minimum category recommended for 10 gigabit Ethernet. This allows for the permanent link design standard of 90 meters.