Classic Amiga 4000 Big-Tower

Assembly Instructions

We congratulate you for purchasing this tower case that was specially designed for the Amiga 4000. It converts the usual hard to expand Amiga 4000 into a professional device offering lots of space for expansions. The new bus board (=daughterboard) features 7 fully usuable Zorro II / III slots (16 / 32 bit), as well as 5 PC-ISA and 2 video slots in the ISA version or 3 ISA and 3 PCI slots and one video slot in the PCI version.

The case offers six 5.25 inch drive bays which are all accessible from outside, and two 3.5 inch drive bays which are also accessible from outside. One of the 5.25 inch drive bay can be occupied by the original Commodore 3.5 inch floppy drive inside a mounting frame, as the height of the drive is 1.5 inch.

Dismantling the A4000 Desktop

After the 2 screws at the back of the case are removed you take the lid off. If there is a harddisk inside, the next thing is to unscrew the harddisk frame and take the harddisk out. Please handle the harddisk very carefully as it is sensitive for mechanical shocks. When removing the disk, take note of the polarity of the data cable.

The beam holding the daughterboard with the slots for expansions cards is fixed with 2 screws and is removed next, then you pull out the daughterboard. Pull out the plugs of the power supply from the mainboard and the drives as well as the data cables of the drives (please note the polarity) and the LED plugs (Key, Power, Disk).

Carefully pull out the CPU board from the motherboard (parallel, not twisted) and keep the plastic pieces as they will be used again. Now you can remove the front assembly by pushing out the 7 plastic hooks.

Then remove the power switch extension pushing rod. Unscrew and take out the drive cage with the drives and remove the drives from it.

Now you take out the screw of the power supply at the backplane of the case and pull out the power supply while moving it towards the front.

Then take off the extension-card holding bracket from the backplane (one screw), remove the 2 hexagonal bolts of the Sub-D type serial port. For this you need a 5 mm plug-on-type key (or pliers). The other hexagonal bolts are NOT removed.

Take out the 9 screws that hold the motherboard and take it out of the case. Please keep the screws as you can use them again. The protective copper shielding around the Sub-D ports and the protective plastic sheet underneath the mainboard are used again later..

Assembly into the tower

First you remove the 6 screws at the back of the case and then take off the lid moving it back and up. The tower frame is then to be layed sideways onto the table.

The dust shielding door at the front of the tower can easily removed temporarily by gripping it with both hands and bending it so far that you can take the hinge-bolts out of the seating.

Take out the bits and pieces underneath the doubled bottom of the daughterboard box of the bus board and sort them. Lay aside the 4 screws with bigger threat measure, later you will mount the plinth of the tower with them. The rest of the screws has a metrical M3 threat.

Now remove the screws of the 3.5 inch drive cage that is underneath the 5.25 inch drive bays and take it out, so you´ll have enough space for mounting the motherboard.

For mounting of the motherboard the hexagonal screws have been installed in the case frame by the factory in exactly the right hole positions of the mainboard. Lay the protective plastic sheet that comes from the bottom of the motherboard onto the bottom of the case frame. Then the motherboard is placed into the case and the screws turned loosely through the holes of the board into the fastly mounted hexagonal screws, so that the board is still moveable. Also turn in the two 1 inch long hexagonal distance bolts underneath the board, at the positions shown in the drawing. They will give additional support to the bus board.

The next thing to do is screwing back in the hexagonal bolts of the Sub-D serial port at the backplane of the case. Please do not fasten the screws too tightly with the 5 mm key (or pliers) as they are easily overturned whereby the threat is destroyed. They should be just as tight as is needed so a fixed plug can be unscrewed and removed without the hexagonals coming loose again. Bring the motherboard into the optimum position and then fasten the M3 screws and the hexagonal distance bolts.

Now plug in the extension cables of the two joystick ports at the left side of the motherboard. Which plug goes in which port can be determined by cable length. Joystick 1 is the MOUSE port, Joystick 2 is the GAME port.

Before the bus board is mounted the cables of the display / switch must be connected to the motherboard. The key-lock switch with the cable colors red / black is to be connected to the "KEY" connector, the green Power-LED with this cable pair colors green / white is to be plugged onto the "PWR" connector, whereby the green wire is plugged onto the middle position of the 3 pins. The red HDD-LED with the cables colors red / white (or red / black) is to be plugged onto the "DISK" connector (see drawing).

Now plug the CPU board with the distance bolds back onto the motherboard. Some revisions of the motherboard have different LED connectors so you should perform a function test before you install the bus board, because the LED connectors and the RAM sockets are covered by the bus board afterwards. If a LED doesn´t work, simply change the polarity of the plug or put the plug one position to the side. Switch the computer off now and install the new bus board into the tower.

To do so push the 100 pin connector into the bus board socket on the motherboard so that it mounts tightly and has a good contact. The bus board is then fixed with the M3 screws onto the holders. The holding edge can corrected in its position by simply loosen the two screws at the rear of the tower.

Next take the both non-conducting red washers and put them onto the two holes that have still remained free over the hexagonal screws. Screw the M3 screws into the threads and fix the bus board. The non-conducting washers are necessary to protect the conductors from a possible short circuit by the big heads of the M3 screws. If there are no washers included the use the original Commodore M3 screws with the small heads instead, which have left over while dismantling the Amiga.

The next step is to mount the original A4000 power supply. Fit the power supply onto the holding construction on the rear of the tower and fix it with two M3 screws. Now connect the power extension cable with the one side to the motherboard and with the other side to the plug of the psu. Fix the cable extension with the two nylon cables ties onto the metal brace of the tower. You can put the clutch of the extension cable into the brace.

At the motherboard plug of the cable extension are 3 pairs of cables. One of them consits of 2 pins the other one of 4 pins. You have now to connect them with the respective plugs. If you do so pay attention that you always connect with conjunction of the wire color. The definition of the cable is as follows:

• Green / White or Black / White = +5V power supply of the MHz display

• White / Blue = Reset

• Red / Black = +12V power supply for the supplementary fan

Change the polarity of the 2 pin connector if the fan doesn´t work..

If you want to use the power supply of the Classic A4000 Tower, the you have to use another fan cover (please order if not included). Take the fan out of its old position and fix it onto the new fan cover. Now screw this with four M3 screws to the second position from the top at the rear of the tower. The power supply of the MicroniK Classic A4000 Tower is fixed to the top position of the tower. In some cases you have to pay attention to different threath. The power switch of the MicroniK Classic A4000 Tower power supply has to be fixed onto the metal sheet which is located behind the power switch button.

The power switch of the original Commodore power supply is operated from the front by a extension plastic rod. Put first the end of the plastic rod with no slit into the back of the power switch button and then the other end with the slit onto the switch of the original Commodore power supply. To fix the plastic rod slide the bold till it fits correctly.

The TURBO switch is just to change the display of the MHz display and is not connected to the A4000.

The original 3.5 inch floppy drive of the A4000 can be mounted directly into a 5.25 inch mounting frame if the height of the original A4000 drive is 1.5 inch. It is also possible to mount the 1.5 inch floppy disk drive into the 3.5 inch drive bays, but in that case you cannot use the second from the front accessible 3.5 inch drive bay. If you have a floppy disk drive with the height of 1 inch then mount it into the 3.5 inch drive bay.

Harddisk drives and additional 3.5 inch slimline floppy drives are now mounted into the 3.5 inch drive bay. Hold the 3.5 inch drive cage onto its mounting position in the tower and determine the position of the drives that have to be placed inside the cage. Then fix the drives into the dismounted drive cage and mount it back into the tower case. Now check the exact positioning of the drives and correct it if necessary.

Connect the data cables and power cables of all drives taking care of the polarity that you noted before.

Configuration of the MHz display

The switch unit with the MHz display at the front of the tower comes completely pre-adjusted. Some A4000 towers are delivered with type 1 or type 2 of the MHz display (mechanical setting). See drawings of the default settings (30 / 40 MHz) next page.

You can set up the MHz display as you like before installing the drives and the 3.5 inch drive cage. You have exactly to set up the jumper configuration to get the right display for each segment of the display. The system of the settings is shown at the drawing above.

For each segment you have to determine one of three possible jumper positions and define whether the segments is always off, only on at "Normal" position, only on at "Turbo" position or whether it is always off.

MicroniK Computer-Service
Brückenstrasse 2
D - 51379 Leverkusen - Germany

Phone: +49 - (0)2171 - 72450
Fax: +49 - (0)2171-724590

E-Mail: Amiga-Support@micronik.de
Internet: www.micronik.de