X68000 Super - CZ-604C

This is a replacement to the two (faulty) X68000 Pro machines that I bought during 2020.

It was advertised on Yahoo Auctions Japan, as usual, with the following images:

The machine was described as:

X68000 SUPER It is a refurbished operation product.
SUPER comes standard with 2M memory and SCSI port.

The power supply unit and control board, which have many troubles, have all electrolytic capacitors replaced, and some resistors, diodes, and transistors > have been replaced.
The backup battery has been changed to CR2032 socket specifications.
Replace the contacts of the power connector, which is prone to damage and poor contact.
Apply grease after disassembling and cleaning the FDD.
Other parts have been cleaned.

Parodius, Detana Twinbee, operation confirmed on SX-WINDOW JOY1, 2 ports OK
Keyboard terminal OK
Mouse terminal OK
AUDIO OUT terminal OK
Headphone terminal OK
24-hour game demo operation OK

* Other detailed operations have not been confirmed only by checking the above operation is.
* The monitor, controller, keyboard, mouse, game, and software used in the operation check are not included.
* Please enlarge the photo to check for scratches and dirt.

An adapter that converts the controller of the Mega Drive to ATARI specifications such as X68000 and MSX is attached.
Cross keys, B and C can be used.

It looks very clean, without any of the normal blemishes, and clearly some effort has been put in to refurbishing it. Fingers crossed that when it arrives it is actually as good as it appears.

[Update 10/03/2021] The X68000 Super landed from Japan. Pictures immediately after unboxing:

[Update 23/03/2021] - Finally got the system mostly connected up and able to test:

• Power on/off control: working
• Video output: clear
• Audio output: clear
• Floppy drive 1: working
• Floppy drive 2: working
• Keyboard: working (via Aranet PS/2 adaptor, Belkin Omniview KVM and Sanwa JPN PS/2 keyboard)
• Mouse: untested
• Joystick: working (via included Megadrive 2-button adaptor)
• SCSI: untested

One problem I did encounter was a very, very loud power supply fan; both a combination of a squealing noise and just a very-tired-bearings-are-shot noise. It will definitely need replacing.

Powering on the system, booting from a Master Disk v3 floppy and a little bit of directory navigation using a PS/2 keyboard adaptor for input.

Trying a game; Gradius II, to make sure that video and audio output is working correctly and testing that the joystick input is okay.

Here's the combined noise of the PSU whine and the original fan:

That's the last 4 seconds of audio from the above initial testing video, amplified by +10dB.

PSU fan was replaced with a Noctua A6x25 FLX to reduce the combined PSU/fan noise. It's a simple job - the only thing to watch out for is changing the 3-pin fan connector of the Noctua to match the 2-pin PSU connector (swap the fan-speed and earth wires on the Noctua, and cut off the fan-speed wire).

It turned out that after replacing the fan, most of the noise was coming from the PSU itself. Now I know that this has had a full capacitor replacement, as it's obvious by the state of the caps and the recent solder job on the underside of the PCB:

Looking more closely, the two middle-side filter caps; C41 and C42, have been replaced with the original values (5600uF, 10v). But, the current recommended wisdom is to uprate these to 6800uF parts, which have been known to cut out PSU noises for several owners…. and this is exactly what I did:

So, did it work?

That's audio taken with the covers off, and the recording made approx 8 inches from the rear of the power supply. Boosted by approx +15dB. There's a tiny bit of white noise from the turbulence from the fan, but it's otherwise silent. I am very happy.

The X68000 Super has 2MB of base memory, compared to the 1MB of the original model, ACE and Pro, so no internal memory module is needed. In addition it has standard SCSI, rather than SASI of the earlier machines; that means I don't need the SCSI controller board that I bought for the Pro, nor does it need the updated loader storing in SRAM to be able to boot from a hard drive.

I've fitted the following upgrades to the Super:

• XSIMM10ss - as fitted with a 16MB SIMM to max the memory out to 12MB
• Sharp CZ-6BM1 - MIDI in/out interface
• Classic PC Club internal SASI/SCSI hard drive cable and mounting hardware
• SCSI2SD v5.1 internal adapter

As my Super model isn't a Super HD, it did not have any of the internal parts needed to fit a hard drive. Namely:

• The SCSI cable only fits from motherboard to back panel - no extension for a HDD.
• No mounting plate to fit a HDD.
• Only a 3-pin PSU cable, not a 4 pin AMP/Molex or Floppy style connector

Other than that, the internals of HD systems and the non-HD versions of the same system (e.g Ace-HD vs Ace, Pro-HD vs Pro, my Super vs Super-HD, etc) are absolutely identical: there is nothing to technically stop a non-HD system being upgraded to HD.

Fortunately there are several ways to get around the missing-parts issue - bodge something yourself, or buy a ready-made kit. I was able to buy a complete set from the Japan-based ClassicPC Club, which contains the following parts:

26-pin to a standard 50-pin SCSI-1 adaptor board and internal SCSI extension cable:

HDD mounting panel and correct screws for the X68000 case and standoffs:

With those in place, I could fit the SCSI2SD adapter in place of a regular 2.5/3.5“ SCSI HDD:

You'll note that there isn't a power connection to the SCSI2SD, that's because the v5.1 SCSI2SD boards can get all the power they need from the built-in SCSI termination signals present on (almost) all SCSI cables. That makes the normal problem of sourcing a 3-pin to 4-pin FDD/AMP/Molex power connector a non-issue.