The first HIPPI standard defined a 50-wire twisted-pair cable, running at either 800Mbps (100 MB/s), but was soon upgraded to include a 1600Mbps (200 MB/s) mode running on fibre optic cable. An effort to improve the speed resulted in HIPPI-6400, which was later re-named GSN (for Gigabyte System Network) but saw little use due to competing standards.
To understand why HIPPI is no longer used, consider that Ultra3 SCSI offers rates of 160 MB/s, and is available at almost any corner computer store. Meanwhile Fibre Channel offered simple interconnect with both HIPPI and SCSI (it can run both protocols) and speeds of up to 400 MB/s on fibre and 100 MB/s on a single pair of twisted-pair copper.