I used to have firewire on some of my older PCs that I used to connect audio interfaces between my guitar and the computer, that was when USB was much slower than later USB2 and USB3 came out.
From memory, as it was a long time ago, there were 4 and 6 wire ports, the 4 wire needed external power but the 6 wired ones were powered from the computer. They were often less problematic than I had with the later USB ones.