FAQ-4 Buying a previously owned Cray System

Cray Research and Cray computers FAQ Part 4


This Cray supercomputer Faq is split into sections, Part 1 describes Cray supercomputer families, Part 2 is titled “Tales from the crypto and other bar stories“, part 3 is “FAQ kind of items“, part 4 is titled “Buying a previously owned machine” and part 5 is “Cray machine specifications“. Corrections, contributions and replacement paragraphs to CrayFaq0220@SpikyNorman.net Please see copyright and other notes at the end of each document. Note: Part 3 was the only part posted to newsgroups. The FAQ was previously hosted at www.SpikyNorman.net


First off, don’t ask me for bits I don’t have any to sell.

So you want to own a Cray machine, here are some notes on what to look for. Firstly decide what you want the beast for, either you are going to seriously try to get it going or you are going to break it up and sell the bits for scrap or profit.

If you want to sell the bits the older Cray-1, Cray-2 and Model D IOS boards are the most desirable being of reasonable size and quantity per chassis. The later liquid cooled YMP Model E, T3d/e and C90s have large and heavy boards (40 Kg). These could be suitable for making into novelty coffee tables but the shipping will cost big bucks. There have been a couple of the early machines broken up and sold for profit. As of Aug 1998 the T3d/e and T90 machines are still in use at customer sites so older machines are likely to be desirable as parts banks for other systems. T90 boards were the most expensive to build and are of compact size so likely to be desirable for the bits-for-the-mantelpiece trade eventually. The Cray-3 boards have poisonous gallium arsenide (GaAs) in the chips.

If you seriously want to get a Cray machine to run for fun, profit or just bragging rights, the ones to aim for are the Air cooled EL-92, EL98 and J90 machines as these will sit in an air cooled room and chew only about 6-10 Kwatts per hour. You will need a chunky power feed, like that suitable for a large electric range cooker, for all except the EL-92 which can run off a normal wall socket. Be sure to check the input power requirement, some machines will be set for European 220 Volts and some for US 110 Volts. Note that ELs may not be Y2K OK at the IO processor level but you might get away with running with the date set to 1990 as there are no time dependant licences in the base Unicos product set. The XMS is just too old and under developed to consider for use.

To have any chance of getting system up and running you will need to have either an already bootable system with the IOS, root and usr filesystems intact or a Unicos release tape and the installation document. Els went up to Unicos 8 and J90s to Unicos 10 so try to get as late a version of Unicos as possible. The compiler products came on separate tapes and are licensed so check for those. Get as many of the books (silver loose leaf binders) as possible and look for the Craydoc/Dynaweb Cds that have the books on. The most important books will be the EL and J90 Basic admin guide SG-2416 and the 3 or more volumes of the system admin guide. The small silver booklet SQ-2162 Cray EL series IOS commands ready reference is also invaluable. If you are buying from the original owner try to get the service and FCO (field change order) history of the machine. Serial numbers are on a plate at the rear of the machine by the power feed point.

The El and J90s were binary release products. You won’t find the src for Unicos on board. The big systems came as either src or binary release but as the binary release licence was cheaper most sites moved to that.

There should be no problems with export restrictions on all but the T3e and T90 systems but some machines used by government Labs won’t have had any import duty paid. Don’t get stuck with that bill !

EL and J90 systems are big (wdh 1270 * 810 * 1500 mm) , very heavy ( 640 Kg ), not waterproof but do have wheels on the base. Spares will be hard to find. You have been warned.

How much to pay ?

Boy that is is a toughie ! There are not many around but then again depreciation on a 4..8 year old computer is visicious. The older mainframe machines went for scrap value plus the cost of taking them away just $1000 or so. These days for an EL ? you tell me when you agree a price then I might have some idea.

Things to look for in an EL.

Check the number of IOSs, the more the merrier so count the number of IOP boards in the VME IOS cage. The IOS boards will be in this order from left to right:

Vme IOS cage board order
Where IOP and IOBB are must have items. 
The DD6S may be replaced by other disk controllers. 
The EI Ethernet interface was standard but FI fddi interface 
was an optional extra as were any other TC tape controller boards.

1 IOS is normal 2..4 IOS systems are not uncommon. There should be a big twin ribbon cable from the each IOS to the Unicos “Large” boards. Count the number of CPUs and the check size of the memory boards. A system must have all its “Large” Unicos card slots filled in order to run but gaps on the right hand side of the VME card cage are acceptable. Unicos Memory board sizes varied from Mem8 ( = 128 Mbyte system ) to Mem64 ( = 2 Gbyte system ) so look carefully the board markings on the visible edge.

Unicos "Large" board order
Missing CPU slots must have a spacer board installed. 
The boards are static sensitive so don't handle them at all without full ESD precautions.

The early ELs have one vector CPU per board, the later have mother/daughter boards with up to total of 8 CPUs in a system. The disk drive generations went mainly ESDI (0.3GB small old), DD4 ( fast IPI ), DD5s ( 5GB scsi Seagate Barracudas ), DD6s ( 9GB scsi ). There should be at least 1 disk controller per four drives. Some sites attached external scsi discs and used a DD_U generic disk driver but there should be some factory fitted drives in the bays. All external disks have to be formatted with 4k block sizes. Above the IOS there will be a small SCSI IOS disk, a QIC or DAT tape drive and sometimes an Exabyte drive. Be very carefull with the QIC tape deck only push the tapes in slowly until they are grabbed by the device and taken in automatically. They are not like the usual slam and clunk QIC tape decks. These IOS tape devices are connected the IOP scsi port but all other devices will have controller boards in the IOS. You may find an EL that looks like two ( or more ) systems welded back to back. These are quite rare and the extra boxes serve as expansion chassis for IOSs and IO devices.

Things to look for in a J90.

J90 systems have 4 CPUs to a module and a bus plug to enable the odd number of CPUs in the last module. The chassis comes in two ( up to 16 CPUs) or four (up to 32 CPUs) parts pushed together. The IOSs are located in drawers at the front, the CPUs pull out from the rear. Each system comes with a Sun-5 SWS system that acts as the console and NFS mounted IOS boot disk, without the SWS you don’t have a viable system. Later J90s have IOS-V “Gigaring” technology. Look for a box(es) with an LCD display and bouncing horizontal Leds on the front that replace the VME cage IOS.

The machines are pretty reliable on the whole, the weak spots being the IOP and IOBBs on the ELs and the Y-1 cables on the J90s.

Other sources of Cray bits and pieces

The Atomic Museum has framed boards for sale at about USD60 when I last looked.

A person called Tony Cole was previously reselling Cray boards in lucite on Ebay. Prices ranged from USD150 for a Cray-1 Memory to about USD 1500+ for a YMP. ** No longer active **

Keep an eye on Ebay, looking just now I see a couple of mugs and posters as well as some boards from a YMP and a whole J90 with a reserve price of USD 8000.

Other Cray items bought and sold

There does seem to be a steady market for Cray manuals and articles. Some pictures of the many Cray branded gifts and promotional items can be found here.

This bundle of stuff went for $2,701.00 at Ebay#184054110 on 10/25/99, 15:45:24. Sold by “frknight”.
Cray 1 Documents picture

I recently came across a notebook containing a number of documents on the supercomputer CRAY-1, including the hardware reference manual – 2240004. All of the documents are included in this offer. The documents are generally in good condition. The specific documents included are as follows:

(1) CRAY-1 Computer System Hardware Reference Manual – 2240004, revision E, dated May 15 1979 – 182 pages,

(2) Promotional documentation explaining the hardware configuration and instruction set, dated 1977 – 12 pages,

(3) Promotional literature featuring Seymour Cray and his Supercomputer which is a reprint of a November 1980 issue of INC. magazine – 8 pages,

(4) A reprinted article from Computer Design – February, 1978 titled “An Introduction To Vector Processing,” by Paul M. Johnson of Cray Research – 9 pages,

(5) A reprinted article from Computer Design – April, 1978 titled “Applications of Vector Processing,” by Lee Higbie of Cray Research -7 pages,

(6) A reprinted article titled ” The CRAY-1 Computer System,” from the January 1978 issue of “Communications of the ACM,” by Richard M Russel of Cray Research – 10 pages,

(7) A reprinted article from Datamation Magazine – October, 1978 titled “The CRAY-1 At Los Alamos” by Fred W. Dorr of the Los Alamos Scientific Laboratory of the University of California – 7 pages,

(8) Five early issues, including the first three, of “Channels,” a quarterly publication of Cray Research, Inc.,

(9) An article titled “Interactive Graphics on the Cray-1 Supercomputer,” submitted by the Los Alamos Scientific Laboratory of the U of Cal. to ACM SIGGRAPH 78 – 17 pages,

(10) An article titled “The CRAY-1 at LASL; An Update,” submitted by the LASL to the AESOP XVI Conference May 2-5, 1977 – 12 pages, and

(11) An article titled “A High-Performance Graphics System for the CRAY-1,” submitted by the LASL to SIGGRAPH 78 – 6 pages. If you have an interest in he historical development, specifications, and operation of the world’s first large-scale scientific computer, the one that placed the word “nanosecond” into common usage.

Do you have similar stuff for sale ? Be sure to post an auction notice in comp.unix.cray to gather the widest audience for Cray Computer related memorbilia.

Trademark Disclaimer and copyright notice

Thank you for taking time to read these important notes.

Cray, Cray Research, CRI, XMP, YMP, C90, T90, J90, T3d, T3e, Unicos, plus other words and logos used in this document are trademarks which belong to Cray Inc. and others. There is nothing generic about a Cray supercomputer.

Some of the ideas described in this document are subject to patent law or are registered inventions. Description here does not place these ideas and techniques in the public domain.

I wrote this document with input from a number of sources, but I get both the credit and the blame for its content. I am happy to read your polite correction notes and may even integrate them with the text so please indicate if you require an acknowledgement.

Personal use of this document is free but if you wish to redistribute this document, in whole or in part, for commercial gain, you must obtain permission from and acknowledge the author.


June 2000 V1.0.5 Lightly dusted on move to WordPress 2021

Copyright (c) 1999 by "Fred Gannett", all rights reserved.
This FAQ may be posted to any appropriate USENET newsgroup, on-line service, web site, or BBS as long as it is posted in its entirety and includes this copyright statement.
This FAQ may be distributed as class material on diskette or CD-ROM as long as there is no charge (except to cover materials).
This FAQ may not be distributed for financial gain except to the author.
This FAQ may not be included in commercial collections or compilations without express permission from the author.

Originally hosted at spikynorman.net

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