Editing DECstation 5000

{{Infobox computer
| name         = DECstation 5000
| image        = [[File:DECstation 5000 Model 200 with cover removed.jpg|260px|frameless]]
| caption      = DECstation 5000/200 with the cover off: KN02 system module and memory on the left, power supply and fans on the right (Adamantios, CC BY-SA 3.0)
| manufacturer = Digital Equipment Corporation
| type         = Workstation
| release date = 3 April 1990 (Model 200)<ref name="wp" />
| cpu          = MIPS R3000 with R3010 FPU at 25 MHz (Model 200)<ref name="kn02" />
| memory       = 8 to 480 MB in 15 memory module slots (Model 200)<ref name="kn02" />
| storage      = External SCSI drives only (Model 200 series)<ref name="mg370_1" />
| expansion    = Three TURBOchannel option slots<ref name="mg370_1" />
| os           = ULTRIX<ref name="wp" />
| power        = 244 W supply (30-32506-01 or H7878A)<ref name="mg370_5" /><ref name="mg38c_psu" />
| dimensions   = 92 × 509.5 × 434.8 mm (Model 200 system unit)<ref name="mg370_a" />
| weight       = 12.7 kg (Model 200 system unit)<ref name="mg370_a" />
| model        = Model 200 (KN02); Model 240 (KN03-GA CPU); Model 260 (KN05-NB CPU); Model 120, 125, 133, 150
| predecessor  = [[DECstation 3100]]
}}
The '''DECstation 5000''' is Digital Equipment Corporation's family of MIPS-based Unix workstations with TURBOchannel expansion slots. The first, the DECstation 5000 Model 200, was announced on 3 April 1990.<ref name="wp" /> The same machines without a graphics option were sold as the DECsystem 5000.<ref name="wp" /> The Model 200 series (Models 200, 240 and 260) shares one enclosure and power supply. The Model 100 series is a smaller design with internal drive bays, its own power supply and its own maintenance guide.<ref name="mg38c_psu" /><ref name="mg32g" />

== History and models ==
The Model 200 series was code-named 3MAX (3MAX+ for the 240 and 260).<ref name="wp" /> The Model 200 has its processor on the KN02 system module itself. The Model 240 and 260 use a separate CPU module: the KN03-GA, running at 40 MHz with 128 KB of cache, in the Model 240, and the R4000-based KN05-NB at 60 MHz in the Model 260.<ref name="mg38c_1" /> The Model 100 series (120, 125, 133 and 150) takes 20, 25 or 33 MHz R3000 CPU modules or a 50 MHz R4000 module, and has internal drive bays and its own H7826-AA power supply.<ref name="mg32g" />

== Model 200 hardware ==
DEC's Model 200 maintenance guide lists the system unit as one system module and chassis, one 8 MB memory module, a power supply with three cooling fans, a removable cover and a front cover plate.<ref name="mg370_1" /> The system module and chassis are a single field-replaceable unit. DEC's warning is never to separate them, as the module then no longer meets FCC emission rules, and never to touch the module's heat sinks, which break easily.<ref name="mg370_5" />

The KN02 functional specification gives these subsystems: an R3000 CPU, R3010 floating-point unit and R3220 memory buffer at 25 MHz; 64 KB instruction and 64 KB write-through data caches; 15 memory array connectors; a 256 KB self-test and bootstrap ROM; a DS1287 real-time clock with 50 bytes of battery-backed RAM; DZ serial lines for keyboard, mouse, communications and printer; a LANCE ThinWire Ethernet interface; a SCSI interface; and three TURBOchannel option connectors.<ref name="kn02" /> Each memory slot takes one 8 MB module (MS02-AA) on the Model 200.<ref name="mg370_5" /> The later Model 200 series guide also lists 32 MB modules (MS02-CA) and a 1 MB NVRAM module (54-20948-01) that must go in slot 14; 8 MB and 32 MB modules cannot be mixed.<ref name="mg38c_1" />

The rear panel carries the on/off switch, the mains inlet, an outlet for the monitor, a DB15 keyboard and mouse connector, two DB25 communications connectors, a reset button, eight red diagnostic LEDs, a ThinWire Ethernet BNC connector, a high-density SCSI-2 connector and the three option slots.<ref name="kn02" /> A green LED on the power supply shows that it is running correctly.<ref name="mg370_5" />

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:100%; text-align:center;"
|+ '''KN02 supply requirements (DEC KN02 specification, Table 3-1)'''
! Supply !! Maximum current !! Typical current
|-
| +5.1 V ±4% || 20.0 A || 16.3 A
|-
| +12.1 V ±4% || 2.70 A || 0.08 A
|-
| −12.1 V ±4% || 0.22 A || 0.04 A
|}
<ref name="kn02" />

DEC gives the KN02's theoretical maximum dissipation as 225 W for a 480 MB machine with three options. The power supply is rated at 244 W DC.<ref name="kn02" /><ref name="mg370_5" /> The system unit takes 100–120 V at 5 A or 220–240 V at 2.4 A, 50–60 Hz, and dissipates up to 359 W.<ref name="mg370_a" />

== Known faults ==
* Power supply failure. Both the Model 200's 30-32506-01 and the H7878A, which DEC calls functionally identical, are switch-mode units with electrolytic capacitors now 30 years old.<ref name="mg38c_psu" /> Rob Jarratt's H7878 shut down after running for a while, then failed outright; he found a failed input smoothing capacitor, leaking capacitors on the output riser board, and output capacitors with high ESR.<ref name="jarratt" /> See [[DECstation 5000 Capacitor Replacement Guide]].
* Overheating. The power supply fans cool the whole system unit. The power-up test reports a hot system as <code>misc/pstemp</code>, and DEC's procedure is to check that all three fans turn.<ref name="mg370_5" />
* Clock and configuration loss. The console stores its settings in the battery-backed RAM of the real-time clock, and DEC's console status code 0439 means "TOD clock values indicate dead battery".<ref name="kn02" /><ref name="mg370_g" />
* Locked console. A forgotten console password is cleared with the clear-NVR jumper (DEC part 12-14314-00) on the system module.<ref name="mg370_2" /><ref name="mg370_b" />
See [[DECstation 5000 Troubleshooting Guide]] for the diagnostic LED codes and test messages, and [[DECstation 5000 General Maintenance]] for routine service.

== Documentation ==
* ''DECstation 5000/DECsystem 5000 Model 200 Maintenance Guide'', EK-370AA-MG-002, October 1990: [[:File:DECstation 5000 Model 200 Maintenance Guide (EK-370AA-MG-002).pdf]]
* ''DECstation/DECsystem 5000 Model 200 Series Maintenance Guide'', EK-PM38C-MG-002, April 1993: [[:File:DECstation 5000 Model 200 Series Maintenance Guide (EK-PM38C-MG-002).pdf]]
* ''DECstation 5000 Model 200 Hardware Operator's Guide'', EK-366AA-OG-002, October 1990: [[:File:DECstation 5000 Model 200 Hardware Operator's Guide (EK-366AA-OG-002).pdf]]
* ''DECstation 5000 Model 100 Series Maintenance Guide'', EK-PM32G-MG-003, April 1993: [[:File:DECstation 5000 Model 100 Series Maintenance Guide (EK-PM32G-MG-003).pdf]]
* ''DS5000/200 KN02 System Module Functional Specification'': [[:File:DECstation 5000 Model 200 KN02 System Module Functional Specification.pdf]]
Contents and coverage of each are on [[DECstation 5000 Documentation]].

== Gallery ==
<gallery mode="packed" heights="200">
File:DECstation 5000-133 with Storage Expansion box.jpg|DECstation 5000/133 with a Storage Expansion box (Stephen Edmonds, CC BY-SA 2.5 AU)
File:H7878 power supply opened (Rob Jarratt).jpg|H7878 power supply opened, fans at the top (Rob Jarratt)
</gallery>

== Related pages ==
* [[DECstation 5000 General Maintenance]]
* [[DECstation 5000 Troubleshooting Guide]]
* [[DECstation 5000 Capacitor Replacement Guide]]
* [[DECstation 5000 Documentation]]
* [[DECstation 3100]]

== References ==
<references>
<ref name="wp">"DECstation", ''Wikipedia'', [https://en.wikipedia.org/wiki/DECstation en.wikipedia.org/wiki/DECstation], citing ''Computerworld'', 9 April 1990, p. 4. Announcement date of the Model 200, code names, DECsystem naming.</ref>
<ref name="kn02">Digital Equipment Corporation, ''DS5000/200 KN02 System Module Functional Specification'', 1990, sections 2 to 4 and 4.5.3 ([[:File:DECstation 5000 Model 200 KN02 System Module Functional Specification.pdf]]). External interfaces, supply requirements Table 3-1, subsystem summary, DS1287 clock.</ref>
<ref name="mg370_1">Digital Equipment Corporation, ''DECstation 5000/DECsystem 5000 Model 200 Maintenance Guide'', EK-370AA-MG-002, October 1990, pp. 1-4 to 1-10 ([[:File:DECstation 5000 Model 200 Maintenance Guide (EK-370AA-MG-002).pdf]]). System unit contents, controls, connectors, option slots, drives.</ref>
<ref name="mg370_2">DEC, EK-370AA-MG-002, pp. 2-20 to 2-22. Erasing a forgotten password with the clear-NVR jumper.</ref>
<ref name="mg370_5">DEC, EK-370AA-MG-002, pp. 5-2 to 5-9 and 5-20 to 5-26. System module and chassis warnings, memory modules, power supply rating, fans, LED, no-power and overheat procedures.</ref>
<ref name="mg370_a">DEC, EK-370AA-MG-002, p. A-2, Tables A-1 and A-2. System unit dimensions, weight, input and heat dissipation.</ref>
<ref name="mg370_b">DEC, EK-370AA-MG-002, pp. B-1 to B-3, Tables B-1 and B-2. Part numbers, including the clear-NVR jumper 12-14314-00 and power supply 30-32506-01.</ref>
<ref name="mg370_g">DEC, EK-370AA-MG-002, appendix G, Table G-2, p. G-5. Minor console status code 0439.</ref>
<ref name="mg38c_1">Digital Equipment Corporation, ''DECstation/DECsystem 5000 Model 200 Series Maintenance Guide'', EK-PM38C-MG-002, April 1993, pp. 1-13 to 1-14 ([[:File:DECstation 5000 Model 200 Series Maintenance Guide (EK-PM38C-MG-002).pdf]]). KN03-GA and KN05-NB CPU modules, memory module types.</ref>
<ref name="mg38c_psu">DEC, EK-PM38C-MG-002, p. 5-20. Power supply rating and the two interchangeable part numbers, 30-32506-01 and H7878A.</ref>
<ref name="mg32g">Digital Equipment Corporation, ''DECstation 5000 Model 100 Series Maintenance Guide'', EK-PM32G-MG-003, April 1993, contents and chapter 5 ([[:File:DECstation 5000 Model 100 Series Maintenance Guide (EK-PM32G-MG-003).pdf]]). CPU module types and the H7826-AA power supply.</ref>
<ref name="jarratt">Rob Jarratt, "DECstation 5000 Model 240 H7878 Power Supply Failure" (27 August 2017), "H7878 Possible Fault Found" (28 August 2017), "PSU Failing Under Moderate Load" (17 September 2017) and "PSU Fixed" (1 October 2017), ''Rob's Old Computers'', [https://robs-old-computers.com/2017/10/01/decstation-5000-model-240-psu-fixed/ robs-old-computers.com]. Repair log of an H7878.</ref>
</references>

[[Category:Digital Equipment Corporation]]