Cat6e doesn't exist.
Cat5, Cat5e, Cat6, Cat6A and Cat7 cables ALL use same RJ45 connector, shielded variants of said cables also use RJ45 except they have the shielding on top of the connector.
What is different between said cables is the maximum speed they can work at. 5 maxes out at 100Mb/sec, 5e maxes out at 1Gb/s as does Cat6.
Cat7 is capable of 10Gb/sec.
Motherboard network cards will 99.9% of time max out at 1Gb/sec though so you wont really benefit from using Cat7 cabling. It will not hurt you either though except maybe as a price since Cat7 will cost more than 5e or 6