I have an old PowerPC Mac from about 1996. It's a beige desktop. I can't seem to find an adaptor for the monitor anywhere, or even what it's called. It's not DB-15 like most Mac's. It's a funny rectangle shape with a bunch of little holes. I'd like to get the old thing running again (was my first computer) but it isn't working too well since my old monitor died. Any help would be apprecieated.

Ok, I finally stumbled onto the answer to my own question. The old mac connecter is called HDI-45 for anyone who would like to know. ;)

Just out of curiosity, what model Mac was this?

I've seen that connector on a bunch of Powerbooks, but never a desktop system. I'd like to know, for nostalgia's sake!


He probably had the 6100 / 7100 / 8100 series. The laptops you refer to had a MONGO-USB like connector, and that is not what he is referring to. This HDI-45 thing ran off of motherboard video, and while it worked, it was not accelerated / optimized graphics. He would be much better off finding the video card of the day, and work with that one. If memory serves, the HDI-45 also used motherboard RAM as video RAM, and that is slower than normal video ram.

All the extra pins were used for the ADB (Apple Desktop Bus -- mice and keyboard) and speaker / headphone jacks. You could plug in the AV monitors, and have these ports on your desk instead of running more cables to the box.

I kept my 7100 using the AV card, and did note a performance drop when I tried the other port. Nice idea, bad performance.

A picture: http://www.welovemacs.com/adp-hdi45.html


I was given a Performa 6115CD with a regular apple monitor (DB15) and searched around for an adapter, you can find an adapter to fit the HDI45 mac connector at web auction sites or from Apple. I found one for $5 including shipping. You can probably find one cheaper if you are super lucky.

Here is the complete info on the adapter, so you can find one.

Apple 391-220 HDI45-DB15, Apple part 922-0721

Apple 391-220 HDI45-DB15 Power Mac Display Adapter (to Mac monitor)
This display adapter is used to connect a standard Apple display to the unique HDI-45 AV monitor port on the back of the following Macs: Power Macintosh 6100 Series ,7100 Series,8100 Series, Performa 61XX Series ,Workgroup Server 6150 Workgroup Server 8150
Apple original part # 590-0796-A

It is a small cable with the funky HDI45 on one end and a DB15 on the other. It hooks up to a normal apple monitor with a DB15 connector.

922-0721 (590-0796-A)
Cable, HDI45 to DB15, Display Adapter is compatable with the following

Performa 6100 Series
Performa 6115CD
Performa 6116CD
Power Macintosh 6100/60, AV
Power Macintosh 6100/66, AV
Power Macintosh 7100/66, AV
Power Macintosh 7100/80, AV
Power Macintosh 8100/100, AV
Power Macintosh 8100/110
Power Macintosh 8100/80, AV
Workgroup Server 6150
Workgroup Server 6150/66
Workgroup Server 8150
Workgroup Server 8150/110


"All the extra pins were used for the ADB (Apple Desktop Bus -- mice and keyboard) and speaker / headphone jacks. You could plug in the AV monitors,"

Anybody have a wire diagram or schematic of the HDI45 pin outs? AV ports would be nice to have on my performa.