Can other elements in my setup affect Internet speed?

The most reliable way of linking components in a local network is with Ethernet, also known as an RJ45 connector. For Ultimate Speed Internet, we suggest using certified Category 5 (preferably Category 5e) network cables, whose specifications reduce crosstalk interference to a minimum. Homemade Ethernet cables should be used with great caution because connections not compliant with T568A or T568B standards are more likely to produce interference.

Router location can also affect Internet speed.