GSC is a bus used in many of the HP 9000

HP 9000

HP 9000 is the name for a line of workstation and server computer systems produced by the Hewlett-Packard Company . The native operating system for almost all HP 9000 systems is HP-UX, a derivative of Unix. The HP 9000 brand was introduced in 1984 to encompass several existing technical...

 workstations and servers. The acronym has various explanations, including Gecko System Connect (Gecko being the codename of the 712 workstation), Gonzo System Connect and General System Connect.

GSC was a general 32-bit

32-bit

The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295. Hence, a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory....

 I/O bus, similar to NuBus

NuBus

NuBus is a 32-bit parallel computer bus, originally developed at MIT as a part of the NuMachine workstation project. The first complete implementation of the NuBus and the NuMachine was done by Western Digital for their NuMachine, and for the Lisp Machines Inc. LMI-Lambda. The NuBus was later...

 or Sun's

Sun Microsystems

Sun Microsystems, Inc. was a company that sold :computers, computer components, :computer software, and :information technology services. Sun was founded on February 24, 1982...

 SBus

SBus

SBus is a computer bus system that was used in most SPARC-based computers from Sun Microsystems and others during the 1990s...

, although it was also used as a processor bus

Memory bus

The memory bus is the computer bus which connects the main memory to the memory controller in computer systems. Originally, general-purpose buses like VMEbus and the S-100 bus were used, but to reduce latency, modern memory buses are designed to connect directly to DRAM chips, and thus are...

 with the PA-7100LC

PA-7100LC

The PA-7100LC is a microprocessor that implements the PA-RISC 1.1 instruction set architecture developed by Hewlett-Packard . It is also known as the PCX-L, and by its code-name, Hummingbird. It was designed as a low-cost microprocessor for low-end systems. The first systems to feature the...

 and PA-7300LC processors. Several variations were produced over time, the later ones running at 40 MHz:

GSC-1X

The original GSC bus implemented on PCX-L and used in the Gecko (712), Mirage (715) and Electra computers. Peak Bandwidth 142MB/s w/DMA, 106 MB/s with PIO writes.

GSC+, aka "Extended GSC" or "EGSC"

Enhancements added for KittyHawk/SkyHawk (U2 chip) that allow for pending transactions. GSC+ enhancements are orthogonal to the GSC-1.5X and GSC-2X enhancements.

GSC-1.5X

GSC-1X with an additional variable length write transaction.

GSC-2X

GSC-1.5X with a protocol enhancement to allow data to be sent at double the GCLK rate, with a peak bandwidth of 256 MB/s.

HSC (High Speed Connect).

Four types of GSC cards were produced.

The GIO cards fit into the larger of the two IO card sockets in the 712 workstation. Several were produced, including a second RS-232

RS-232

In telecommunications, RS-232 is the traditional name for a series of standards for serial binary single-ended data and control signals connecting between a DTE and a DCE . It is commonly used in computer serial ports...

 serial port, a serial/10BaseT

10BASE-T

Ethernet over twisted pair technologies use twisted-pair cables for the physical layer of an Ethernet computer network. Other Ethernet cable standards employ coaxial cable or optical fiber. Early versions developed in the 1980s included StarLAN followed by 10BASE-T. By the 1990s, fast, inexpensive...

 combo, a second graphics card and a Token Ring

IBM token ring

thumb|Two examples of token ring networks: a) Using a single [[Media Access Unit|MAU]] b) Using several MAUs connected to each otherthumb|Token ring networkthumb|IBM hermaphroditic connector with locking clipthumb|An IBM 8228 MAU...

 card.

The 715/Mirage, 725, 735, 755, B, C and J class workstations and the D and R class servers used the so-called "EISA form factor". Many different types of card were produced, including Gigabit Ethernet, single and dual 100Mbit Ethernet, Ultra-2 SCSI

SCSI

Small Computer System Interface is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, and electrical and optical interfaces. SCSI is most commonly used for hard disks and tape drives, but it...

, ATM

Asynchronous Transfer Mode

Asynchronous Transfer Mode is a standard switching technique designed to unify telecommunication and computer networks. It uses asynchronous time-division multiplexing, and it encodes data into small, fixed-sized cells. This differs from approaches such as the Internet Protocol or Ethernet that...

 and graphics.

The K-class and T-class servers both used the "3x5" form factor, although the different brackets prevent the cards being interchangeable. Fibre channel

Fibre Channel

Fibre Channel, or FC, is a gigabit-speed network technology primarily used for storage networking. Fibre Channel is standardized in the T11 Technical Committee of the InterNational Committee for Information Technology Standards , an American National Standards Institute –accredited standards...

 and Gigabit Ethernet cards both exist.