---
title: Cray Research T3D
categories:
- Computers
types:
- Professional Computer
origins:
- U.S.A.
years:
- '1993'
cpus:
- 32 to 2048 DEC Alpha RISC processors
params:
  name: T3D
  image: /media/museum/photos/cray_t3d_system_s1.jpg
  company: /companies/cray-research
  company_name: Cray Research
  specs:
  - label: NAME
    value: T3D
  - label: MANUFACTURER
    value: Cray Research
  - label: TYPE
    value: Professional Computer
  - label: ORIGIN
    value: U.S.A.
  - label: YEAR
    value: '1993'
  - label: END OF PRODUCTION
    value: '1999'
  - label: BUILT IN LANGUAGE
    value: None
  - label: KEYBOARD
    value: Video terminal
  - label: CPU
    value: 32 to 2048 DEC Alpha RISC processors
  - label: SPEED
    value: 150 MHz (processors) 19.2 to 307.2 GFLOPS (global system)
  - label: RAM
    value: 2 to 128 GB
  - label: TEXT MODES
    value: Depending on the video terminal
  - label: SIZE / WEIGHT
    value: 1.9 m² per cabinet (1 to 4 cabinets)
  - label: I/O PORTS
    value: '2 to 32 I/O gateways - Peak I/O bandwidth: 12.8 Gbytes/s'
  - label: OS
    value: UNICOS MAX
  - label: POWER SUPPLY
    value: PSU and cabinet cooled by computer coolant fluid (3M Fluorinert)
  - label: PRICE
    value: Unknown
  comments:
  - author: Jimmothy Parr (canadian)
    date: Tuesday 11th May 2021
    text: great PC! does it come with the guy? /gen
  - author: Digby (Hong Kong)
    date: Tuesday 11th May 2021
    text: i was born...!
  - author: Yannis (Greece)
    date: Wednesday 30th January 2013
    text: Twenty years later (2013) a computer of equivalent performance in GFLOPS would take up to sixteen average processors (eg. Core i3 \~ 3 GHz) to build. Obviously less than 2048 CPUs, but it shows that this machine can still be called a supercomputer in terms of performance, even twenty years after its production.
  - author: jonjon (alabama)
    date: Saturday 25th November 2006
    text: i worked with this computer and yes i hated it and when our company threw out or to get it to a refubishing company i bout it agin and it is in my basement but i like it now
  oc_id: 991
  source:
    url: https://web.archive.org/web/20230529194852/http://www.old-computers.com/museum/computer.asp?c=991
    date: '2023-05-29'
---

With the T3D, Cray research introduced a new generation of Massively Parallel Processor (MMP) super computers.

The T3D integrated from 32 to 2048 processing elements (PE's). Each PE was composed of a DEC 21064 RISC chip, also known as DEC Alpha, with its own memory area, memory controller, and prefetch queue.

The DEC Alpha contained a floating point unit, an integer unit, both with 32 64-bit registers, a 128-bit bidirectional bus, and both instruction and data caches.

The PE's were combined in nodes of 2 PE's running at 150 MHz, along with two to 64 megabytes of memory and a network switch. The nodes were connected in a 3-D torus network configuration.

Memory was physically distribued among the processors, but was globally addressable (any processor could address any memory location in the system.

The global peak performance of a T3D was from 19 (128 PE's) to 307 (2048 PE's) GigaFlops (billions floating-point operations per second).

The system ran UNICOS MAX, the Cray Research's operating system. Each processor ran a minimal microkernel to handle frequently used functions, interprocessor communication and memory management. Major programming language were C and Fortran compilers

The T3D was tightly coupled to a CRAY **C90** or CRAY **Y-MP** host system through a high speed channel, making host's resources (I/O functionality, I/O subsystem, high-speed disks) directly available to the T3D.

The Cray T3D was replaced by the **T3E**, the first supercomputer to sustain one teraflop (1 trillion F.P. calculations per second).

<table> <tr> <td></td> <td>We need more info about this computer ! If you designed, used, or have more info about this system, please send us pictures or anything you might find useful.</td> <td></td> </tr> </table>