[mchristen]

There has to be something else going on here because I routinely achieve > 800mbps on my gigabit network over copper.

[adrianmonk]

I'm not a hardware engineer, but from some quick research it appears that 100 megabit ethernet ("fast ethernet") transmits at effectively 125 MHz. So the 100 megabit number describes the usable bit rate, not the electrical pulses on the wire.

Gigabit Ethernet is more complicated, and it uses multiple voltages and all four pairs of wires bidirectionally. So it is not just a single serial stream of on/off.

[jws]

Yes, the wire symbol rates are higher. For instance, 100mbit Ethernet has a 125 million symbols per second wire rate.