A4000T/040 by Commodore
A4000T/040 by Amiga Technologies
A4000T/060 by Amiga Technologies

In 1994 April Commodore stopped the production of all Amiga models. Until 1995 May no Amigas were produced when the new owner, Escom, created a division called Amiga Technologies and restarted the production of the A4000T and A1200.
There are minor differences only between the CBM and Escom machines. The Commodore one has a more stylish case and high density floppy drive while the Escom one has more drive bays and option for an 060 processor card instead of an 040 one. The picture above shows the original Commodore model.


68040 @ 25-40 MHz
68060 @ 50-56 MHz
PowerPC 604e @ 150-233 MHz

All A4000T models' processor is mounted on a removable processor card. The A4000T/040 were originally equipped with an A3640 v3.2 processor card featuring a 68040 @ 25 MHz on them while the A4000T/060 with a Quikpak 060 card featuring a 68060 @ 50 MHz.


2 MB Chip RAM
up to 16 MB Fast RAM on motherboard
up to 128 MB Fast RAM on processor cards
up to 1,25 GB Fast RAM on Zorro III expansion cards

The A4000T has 2 MB 70 ns Chip RAM soldered to its motherboard and four 72 pin SIMM sockets for Fast RAM expansion. The sockets accept industry standard 32 or 36 bit page mode SIMMs. The four parity bits of the 36 bit modules are ignored and they function as simple 32 bit ones. EDO RAM is not supported by the motherboard RAM controller.
The four Fast RAM sockets accept 1, 2, 4 or 8 MB modules up to a total of 16 MB Fast RAM. The SIMMs cannot be mixed and the 8 MB ones have to be placed in every second socket.
The access speed of the Fast RAM on the motherboard can be controlled by software, either 80 or 60 ns.
The Quikpak processor card in the A4000T/060 has four SIMM sockets which can accept up to 128 MB EDO RAM.

Custom chips

Alice - AGA display controller
Lisa - AGA display encoder
Paula - audio and I/O controller
Fat Gary - system address decoder
Super Buster - DMA arbitrary controller
Ramsey - RAM controller
Bridgette - complex buffer

Supported screen modes
320×256 - 1280×512
320×200 - 1280×400
320×200 - 1280×400
50 Hz, 15.60 kHz
60 Hz, 15.72 kHz
73 Hz, 15.76 kHz
15 Hz, 15.72 kHz
320×512 - 640×1024
320×400 - 640×800
640×480 - 640×960
640×400 - 640×800
400×300 - 800×600
50 Hz, 29.45 kHz
59 Hz, 29.20 kHz
60 Hz, 31.44 kHz
70 Hz, 31.43 kHz
72 Hz, 24.62 kHz
Supported palettes
256 from 16 million, 262144 (HAM8)

All A4000Ts have Kickstart 3.1 ROM. The access speed of the ROM is selectable by a jumper, either 160 or 200 ns.
All A4000Ts have Super Buster revision 11 chips avoiding all the Zorro III DMA problems of early A4000 desktop models.

Expansion slots

1× processor card slot
5× Zorro III slots
2× extended video slot
4× inactive ISA slots

The Zorro, ISA and video slots are all placed on the motherboard. The two video and three ISA slots are in line with a Zorro III slot.
The two video slots are the same extended ones found in A4000 desktop models.
The four ISA slots have their power and ground pins activated only. In order to access the slots by the A4000T a BridgeBoard has to be installed. With an installed BridgeBoard three ISA AT compatible cards can be used in the remaining slots. Inactive slots can be used for non intelligent cards like TBCs or fan cards.
The processor card slot is physically the same 200 pin one which can be found in the A3000. The A4000T leaves more room for the processor cards than the A4000 desktop which the Quikpak card in the A4000T/060 takes advantage of.

The A4000T has a vast array of upgrade options, including processor cards, SCSI controllers, retargetable graphics cards, video digitizers, ethernet cards and many other types of expansion.

Drive bays

3× 5.25" horizontal front bays
2× 5.25" vertical front bays
1× 5.25" vertical rear bay

The Commodore A4000T does not have a rear drive bay.
One of the horizontal front bays is occupied with a 1.76 MB high density floppy disk drive in the Commodore A4000T and with a 880 kB double density one in the Escom A4000T. The A4000T shipped with a 3.5" SCSI 2 or IDE hard disk drive installed in one of the vertical bays.


1× serial DB25 male, RS232
1× parallel DB25 female, Centronics
1× video DB23 male, analog RGB
2× mouse/game DB9 male
2× stereo audio RCA jack
1× keyboard 5 pin female DIN
1× external SCSI DB50
1× internal SCSI 50 pin header
1× internal floppy 34 pin header
1× internal AT IDE 40 pin header
1× internal audio input 3 pin header

The built in IDE controller supports two IDE devices connected simultaneously. Unlike the A1200 the A4000T has a buffered IDE port. Only mode PIO 0 is supported.
The built in Fast SCSI 2 host adaptor (NCR 53710) supports 7 SCSI devices connected simultaneously. The controller uses active SCSI termination.
Although the floppy drive controller supports up to four devices, only two drives can be attached to the internal floppy header as there is no external floppy connector present. Both double and high density disk drives are supported.
The internal audio connector enables an audio expansion device mounted internally (e.g. CD-ROM, sound card) to mix its output into the standard Amiga audio output.

Other components

power supply: Commodore A4000T: 250 W power output
Escom A4000T: 200 W power output
monitor power connector
6× standard 4 pin power connectors
additional fan for better air circulation in the case
0.25 W internal speaker
speaker disable switch
reset switch
lithium battery for the clock

Motherboard revisions

revision 4 (Photo)