@Jlindemann -- for your account, your cable-modem is internally configured to limit the speed between the cable-modem and Shaw's network to 1 Gbps for downloads, and 100 Mbps for uploads to the Internet.
If you upgrade your account to "Shaw Gig 1.5", your cable-modem will receive at 1.5 Gbps. So, if you have two devices (routers or computers) that are Ethernet-connected to the cable-modem, they will "share' the speed, e.g., 750-plus-750 or 500-plus-1000.
If you have the latest cable-modem, it has one 2.5 Ghz port. Use a "CAT-6" Ethernet cable to connect to the network adapter inside the computer that is faster (and much more expensive) than the standard 10/100/1000 network adapter. Then, you will be able to receive at the 1.5 Gbps speed.
However, note that most server computers on the Internet have 10/100/1000 network adapters. So, they cannot "push" out data at more than 1 Gbps. Also, most of those server computers have multiple simultaneous sessions, servicing multiple users. So, if you have 10 users downloading from one server, they each may only get 1/10 of the 1 Gbps speed.
You'll have to consider FTTH (Fiber optic cable To The Home) to receive at "light-speed", and you'll have to connect to computer servers that have fiber-optic network adapters. Of course, all the routers within Shaw's infrastructure would have to have fiber-optic network adapters, to avoid them being a "bottle-neck" between the server and your home computer.
