The "Commodore ITX-64"
By Neil Jansen
Posted on April 28, 2003
Jump to:

Mounting the motherboard

Believe it or not, this is the fifth motherboard that's been inside this case!

I'd say the biggest problem with mounting a newer motherboard in an older vintage computer is how to go about interfacing the new ports to the old ports. In fact, there's not one port in the whole system that I didn't have to modify in some way! Some were harder than others, but I managed to get them all done without too much trouble.

Slot-load DVD with 5¼" floppy face

This still has to be my favorite part. I decided to stealth the DVD by replacing the plastic piece with the original 5¼" floppy face. Even the big ugly red LED still works!

Interfacing signals

This is what I came up with.... A little circuit board that adapts the older joystick/serial/video ports to newer ATX-style connectors. This keeps the project stealth, and at the same time makes my life easier since I don't have to open the thing up to plug/unplug a cable. The NTSC video and left/right channels come out of the "Video" DIN plug, and the USB comes out of the "Serial" DIN plug... The ethernet adaptor has to pass through the second 9-pin joystick port, so I used a 9-pin 'dumb terminal' adaptor to bring this back to an RJ45 connection.

I was concerned about possible ghosting through the monitor extension cable, so I decided to use milspec shielded wire for the three analog signals. It turned out so good, that I can run it at 1600x1200 with no noticable ghosting. I'm definately impressed!

Power Supply

Since the original C64 was completely fanless, that means no fans in the new power supply! At the time, the power supply pictured above seemed like my best bet, but at only 55 watts, i can't simultaneously power my HDD, full size DVD drive, and CRT (which runs off of 12v), without the system rebooting. When I get some free time, i'll design my own power supply, which will sit exactly where the original one did.