Commodore Amiga 2000 Teardown

In 1986-87, Commodore released the Amiga 2000. The machine was technically similar to the Amiga 500, but had a larger case and was designed to be more expandable. Costing around $1,500 (US), the Amiga 2000 was designed to compete with the much more expensive Apple Macintosh II (~$5,500) and IBM PC (~$3,000). Follow along as we crack open the second generation he Amiga 2000--the Amgia B2000-CR.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The Amiga 2000 was designed to be the high-end version of the Amiga 500 and successor to the popular Amiga 1000.

We purchased this Commodore Amiga 2000 (B2000-CR) for about $200 from an online auction. It arrived without a keyboard, documentation, or software.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Along the front of the Amiga 2000 are the power and hard disk activity lights, two bays for 3.5" disk drives, one bay for a 5.25" drive, 5-pin DIN femal keyboard port, and two DE-9 RS-232 serial ports (used for a mouse or other controller).

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The plastic housing for the Power and Hard Disk activity lights doesn't sit flush with the front cover on this Amiga 2000. We'll have to take the cover off to see what's causing the problem.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The Amiga 2000 can accomodate two 3.5" drives and a single 5.25" driver. This unit has two 3.5" drive, but no 5.25" drive--thus the rectangular plastic panel below the two 3.5" drives.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The Amiga 2000 has a 5-pin DIN female keyboard port and two DE-9 RS-232 serial ports (for a mouse, joystick, or other controller).

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Other than the two case srews, there's nothing of note on either side of the Amiga 2000.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Along the back of the Amiga 2000 are the power switch, C14 power inlet, power supply cooling fan vent, and external ports.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The following ports are located on the back of the Amiga 2000:

• Video: DB-23 male (Analog RGB)
• Parallel Port: DB-25 female (Centronics)
• Disk Drive: DB-23 female (external floppy drive)
• Mono Video: Composite (black and white)
• Stereo audio RCA jacks
• Serial Port: DB-25 male RS-232

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The Amiga 2000 has nine expansion slots, broken down as follows:

• Five Zorro II (proprietary) slots
• Two 8-bit ISA slots
• Two 16-bit ISA in line with Zorro II slots

None of the slots are being used on this machine.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

There is a lot of dust on the inside of this Amiga 2000's PSU cooling fan. This doesn't boad well for the cleanlines of the other internal components.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The first step in cracking open this Amiga 2000 is to remove the two screws on each side of the metal case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

A single case screw is located on the back of the Amiga 2000. Unfortunately, someone installed this machine's case without first removing the screw.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

After removing all the external case screws, you can lift the top of the metal case away from the Amiga 2000.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the top half of the case and attached front cover removed, we can see this machines two 3.5" disk drives and the plastic housing for the Power and Hard Drive activity lights.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

There is a lot of dust inside this Amiga 2000's case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The Amiga 2000's Power and Hard Disk activity lights are mounted on a plastic stand that sticks out from the internal metal case. Despite the presence of a Hard Disk activity light, this machine did not come with an internal hard drive.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Looking at the Amiga 2000 from the side, we can see part of the motherboard. Some of the board is covered with a large metal frame, which holds the power supply unit, two 3.5" drives, and 5.25" drive (if one was present).

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

More dust has accumulated on the motherboard.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

This Amiga 2000 definitely wouldn't have worked in this condition. It seems that a previous owner disconnected most of the 3.5" disk drive cables before shipping the machine.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Before removing the 3.5" disk drives, we'll need to disconnect that power and data cables. As I noted on the previous photo, someone had already detached most of the drive cables. I'll remove the loan power cable that remained attached.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

A small circuit board is attached to the end of the ribbon cable. Neither of this cable's connectors were attached to the 3.5" drives.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The both the ribbon cable and the small circuit board have 34-pin female connectors--matching the 34-pin male connectors on the two 3.5" drives. I'm not 100 percent sure of the the circuit board's function, but it could simply facilitate the connection of drives when mounted next to each other--instead of on top of each other.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With all the cables disconnected, we can remove the metal plate holding the Amiga 2000's two 3.5" drives. Four screws (two on each side) hold the disk drive mounting plate to the internal metal frame.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With all four screws removed, we can lift the mounting plate, and attached drives, away from the Amiga 2000's internal metal frame.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Four screws hold each of the Amiage 2000's 3.5" drives to the mounting plate.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the screws removed, the Amiga 2000's 3.5" drives can be separated from the mounting plate. Small plastic spacers were used on the thinner drive (right).

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Like the other internal surfaces on this Amiga 2000, the 3.5" drive mounting plate is covered with dust.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

One of the 3.5" disk drives in this Amiga 2000 was a Fujitsu M2532K-19A.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Even if I had connected all the cables and powered on this Amiga 2000, I doubt its Fujitsu M2532K-19A drive would have worked. A thin wire soldered to the underside of the drive appears to have melted and torn. Note the charred shielding and broken wire.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The second 3.5" disk drive in this Amiga 2000 was a Chinon FB-35A. Although the company dabbled in computer compents and peripherals, Chinon was best known in Japan as a camera manufacturer.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the 3.5" drives and mounting plate removed, we'll turn our attention to the large, internal metal frame, which also holds the power supply.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Three screws hold the front of the metal frame to the lower half of the Amiga 2000's metal case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Four screws hold the back of internal metal frame to the lower half of the Amiga 2000's metal case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the seven screws removed, you can lift the internal metal frame away from the Amiga 2000's case. Before we can completely separated the frame of the case, we'll need to disconnect the motherboard's power cable.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

You'll need to disconnect the motherboard's power cable before completely removing the Amiga 2000's internal metal frame and attached power supply.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Two screws should hold the Amiga 2000's power supply securely to the internal metal frame, but one of the screws in missing and the other is connected only to the frame and not the power supply.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

As no screws are holding the Amiga 2000's power supply to the internal frame, we can lift the supply away from the frame.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

This Amiga 2000 has an Elec & Eltek 420504-SD power supply.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

While I normally recommend you don't crack open PC power supplies, I'm going to carefully remove this supply's cover

Warning: Computer power supply units (PSUs) contain components that can deliver dangerous electric shocks. The capcitors inside most PSUs can retain an electrical charge for a long time after being removed from a power source. You should never open or work on a PSU without proper training.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Note the warning label of the other side of the Amiga 2000's power supply unit.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the cover removed, we get our first look inside the Amiga 2000's power supply unit. Remember, look but don't touch!

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Wow. There's a lot of dust and grime inside this Amiga 2000's power supply unit. I will not be cleaning, or even touching these components.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the internal metal frame and attached components removed, we can finally see the entire Amiga 2000's motherboard.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Before removing the motherboard from the lower half of the Amiga 2000's case, we'll need to disconnect the ribbon cable for the two 3.5" disk drives.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

We'll also need to disconnect the cable for the Amiga 2000's Power light. Although this Amiga 2000 has a Hard Disk activity light, it did not come with a hard drive. A SCSI hard drive was available on A2000HD systems.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the Power and Hard Disk activity light cable disconnected, you can pop the plastic stand off the lower half of the Amiga 2000's metal case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the internal metal frame, drives, power supply, and cables removed, we can begin removing the Amiga 200's motherboard from the lower half of the case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Several screws hold the Amiga 2000's motherboard and attached plate to the lower half of the case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Once you've removed all the screws holding the the motherboard to the case, you'll also need to remove the bottom screws from the expansion slot covers above the rear ports. These metal covers slightly overlap the metal shield that surrounds the rear ports. You don't actually need to remove the three covers, just remove the lower screw and then swing the covers up enough to slide out the motherboard and attached metal plate.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Once you've removed motherboard screws and pushed aside the expansion slot covers, you can lift the motherboard away from the Amiga 2000's case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

With the motherboard removed, there's nothing left inside the lower half of the Amiga 2000's case.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

This Amiga 2000 (B2000-CR) has five Zorro II (Amiga proprietary) slots, two 16-bit ISA slots, two 8-bit ISA slots, one video slot connector, and one 32-pin disk drive connector. The four ISA slots will only provide power to attached cards. The Amiga doesn't have the ability to navtively communicate with these type of cards. However, using a Commodore bridgeboard the slot could be activated and used.

As with all the surfaces within this machine, the motherboard is covered with dust. Before taking any close-up shots of the chips, I'm going to spen a little time and effort cleaning off the dust.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

After 20 minutes of blowing and wiping away the dust, this Amiga 2000 motherboard looks much better.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

I'm going to leave the metal plate attached to the bottom of the motherboard. There's really nothing put solder points under it.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Now that we have cleaner motherboard, let's take a look at the chips on this classic Amiga 2000.

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

The Amiga 2000 used a 7.16 MHz Motorola 68000 processor. In addition to Motorola, several companies also manufactured the chip. From this chip's markings, I believe it is a 68000 microprocessor manufactured by Signetics. This chip has the markings:

S
SCN68000C8N64
QFJ1385
8729KD

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

I believe this chip is the NEC 315093-02 256K ROM that contains the Amiga 2000's Kickstart code. It has the markings:

NEC
Japan 8939ED
315093-02 297
1988 CBM

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

These two chips are the MOS Technology 8362 (Denise Display Encoder) and MOS Technology 8364 (Paula Port Audio UART and Logic chip).

The have the markings:

MOS
8364R7
3087 27

MOS
8362R8
3087 28

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

This Amiga 2000 has the following markings on the motherboard:

AMIGA B2000-CR
HAYNIE/FISHER
A/W 312723 REV 4.1

The original Amiga 2000 (A2000) was designed and manufactured in Germany. It was based on a German Amiga 1000 motherboard. But not long after launch of the A2000, Commodore engineers redesinged the machine, using technology from both the original German design and the Amiga 500.

The first set of markings denote this machine as a redesigned Amiga B2000-CR (Cost Reduction). But more interstingly, the markings "HAYNIE/FISHER" refer to Commodore engineers who worked on the B2000-CR. Dave Haynie was primary engineer on the Amiga B2000-CR (Cost Reduction), and Terry Fisher designed the motherboard.

This is the first time I have seen the names of a computer's designers printed on the machine's motherboard.

For more information on the history of the Amiga 2000, including several quotes and posts from Dave Haynie, check out the following links:

• Amiga 2000 - Wikipedia
• A history of the Amiga, part 6: stopping the bleeding  - ars technica (great posts by Dave Haynie)
• Commodore Amiga 2000  - Amiga History Guide
• Commodore Amiga 2000 - Old-Computers.com
• Dave Haynie - Wikipedia

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler

Photo by: Bill Detwiler / TechRepublic
Caption by: Bill Detwiler