Editing Acorn Archimedes A4000 Maintenance Guide (section)

== The machine and its board ==

The ARM250 integrates the four chips that were separate on the [[Acorn Archimedes A3000]] &mdash; the ARM2 core, MEMC1a, VIDC1a and IOC &mdash; into one package running at 12&nbsp;MHz.<ref name="chris" /> Because of this, there are no socketed processor-family chips: a failure inside the ARM250 means replacing the whole device. The board is part '''0194,600''' ("Roadrunner"), the same board used by the A3020.

<templatestyles src="Template:StyledTable/styles.css" />
{| class="wikitable styled-table" style="width:90%; text-align:center;"
|+'''Acorn A4000 key facts'''
! Item !! Detail
|-
| Processor || ARM250 @ 12&nbsp;MHz (integrates ARM2 + MEMC1a + VIDC1a + IOC)
|-
| RAM || 2&nbsp;MB standard, expandable to 4&nbsp;MB
|-
| ROM || RISC OS 3.11 (2 ROMs)
|-
| Storage || 3.5" floppy (Citizen OSDA-75G-U) + internal IDE hard disc
|-
| Hard disc (by model) || AGC20 80&nbsp;MB, AGC40 105&nbsp;MB (Conner CFS105A), AGC50 210&nbsp;MB (Conner CFS210A)
|-
| Expansion || one mini-podule slot; optional Econet
|-
| PSU || separate cased switch-mode module
|}