# XP/S5
**Wikidata**: [Q69817262](https://www.wikidata.org/wiki/Q69817262)  
**Source**: https://4ort.xyz/entity/xp-s5-q69817262

## Summary
The XP/S5 is a supercomputer manufactured by Intel. It operates on the OSF/1 operating system and utilizes a architecture of 66 processor cores. During the mid-1990s, the system achieved a peak performance of 3.3 gigaflops.

## Key Facts
*   **Classification:** Supercomputer
*   **Manufacturer:** Intel (American multinational technology company)
*   **Operating System:** OSF/1 (a variant of Unix developed by the Open Software Foundation)
*   **Processor Cores:** 66
*   **TOP500 System ID:** 864
*   **Peak Performance (Rpeak):** 3.3 Gigaflops (recorded in June 1994, November 1994, and June 1995)
*   **Max Performance (Rmax):** 2.06 Gigaflops (recorded in June 1994 and June 1995)

## FAQs
### Q: What type of computer is the XP/S5?
A: The XP/S5 is classified as a supercomputer. It was built by the technology company Intel.

### Q: What operating system did the XP/S5 run?
A: The XP/S5 ran on OSF/1, which is a variant of the Unix operating system developed by the Open Software Foundation. Documentation also links the system to the class of operating systems known as Tru64 UNIX.

### Q: How powerful was the XP/S5?
A: The XP/S5 had a peak performance (Rpeak) of 3.3 gigaflops. Its maximum sustained performance (Rmax) reached 2.06 gigaflops during benchmarks conducted in 1994 and 1995.

## Why It Matters
The XP/S5 represents a specific era of high-performance computing history in the mid-1990s where commercial manufacturers like Intel were directly producing large-scale supercomputer installations. Its inclusion in the TOP500 supercomputer records (System ID 864) marks it as a verified, rankable system of its time.

The machine is significant for its use of the OSF/1 operating system, highlighting the reliance on Unix variants for high-speed computation before the widespread dominance of Linux in later decades. Furthermore, its manufacture by Intel demonstrates the company's historical involvement in building complete supercomputer systems beyond just the semiconductor components, leveraging its expertise in processor technology to build a machine with 66 cores capable of gigaflop-scale calculations.

## Notable For
*   **Intel Manufacturing:** Unlike many supercomputers that are assembled by specialized HPC firms using commodity chips, the XP/S5 was manufactured directly by Intel.
*   **OSF/1 Integration:** It utilized OSF/1, a significant Unix variant developed by the Open Software Foundation, distinguishing it from systems running proprietary Unix flavors common in that era.
*   **TOP500 Ranking:** It is a recorded entity on the prestigious TOP500 list of supercomputers.

## Body

### Hardware Specifications
The XP/S5 was engineered as a high-performance supercomputer. The system architecture relied on a parallel processing configuration comprising **66 processor cores**.

The system was manufactured by **Intel**, a major American technology corporation headquartered in Santa Clara, California. Intel, founded in 1968, utilized its semiconductor industry expertise to construct this system during the mid-1990s.

### Performance Data
The XP/S5 was benchmarked multiple times between 1994 and 1995, appearing on the TOP500 list with system ID **864**.

*   **Rpeak (Theoretical Peak):** 3.3 Gigaflops
*   **Rmax (Max Sustained):** 2.06 Gigaflops (June 1994, June 1995); 2.0 Gigaflops (November 1994)

### Software Environment
The XP/S5 operated using **OSF/1**, a variant of the Unix operating system. OSF/1 was developed by the Open Software Foundation.

In the context of its software classification, the system is also associated with **Tru64 UNIX** (formerly OSF/1), an operating system for the Alpha family of processors that was inceptioned in 1992. The reliance on this OS indicates the XP/S5's role in the broader Unix-based computing ecosystem of the 1990s.