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Performa 5200 repair? (psu broke)
I did some work to get a 80w micropsu to run a ”portable 5200” (bluescsi and db15 to hdmi capture so the screen is on my laptop).

However, I would want my 5200 with CRT to work again. Its original PSU said bzzzzzzt when I plugged it - as if it was shorted. I am thinking best would probably be to replace the PSU, but that it might need things a normal ATX does not provide for the crt (analog board)?

If I am lucky someone has already done this and knows what to do 🙏

Posted by: noglin on 2025-05-16 07:56:40
Probably time to spend a moment looking at the 5200 analogue board in detail, see for any obvious shorted components or cap goo. The CRT (and motherboard) is heavily dependent on this to run.

Posted by: Byrd on 2025-05-16 17:40:14
The analogue board might have suffered as well, true. But the PSU is broken for sure.

To fix the PSU I think my options are:
- repair the original PSU (I've never done such work before)
- get a working original PSU with the matching revision (which will eventually fail or need re-cap)
- replace the original PSU with an ATX, I've done that to drive the motherboard, and it was very helpful to read how others had accomplished that.
- give up and just treat it as a 6200, get an apple monitor to go with it.. but sad.. 5200 was my first mac..

I think replacing with an ATX is the better option, if it is possible. If my original PSU was still working, I could hook it all up and measure the voltages to see what the analogue board needs and, if I'm lucky it only needs the 5V/12V that ATX supplies.

If someone has already done the work to figure out how to drive the analogue board with an ATX and knows the pin-outs and voltages that would help a lot.

Posted by: noglin on 2025-05-17 03:37:42
Hello,

Any progress in your project?

I'm curious because I would like to do pretty much the same.

I was donated the motherboard of a Performa 5200 and its PSU.
The motherboard is clean with the ROM and the RAM present. Maybe I will have to recap it.
However everything else is missing: no casing, no CRT and no cables at all.
It means I cannot connect the PSU to the motherboard as of now.

Do you have any suggestion on how to connect an ATX ?

More generally have you found any documentation, schematics or pinout of the harness and various connectors ?

here are interesting readings I found sofar
lowendmac.com

Performa 5200 - Low End Mac

The 75 MHz Performa 5200 was the first PowerPC Mac with an integrated monitor. Although the PPC 603 CPU was superior to the older 601, this computer’s architecture kept performance of the 5200 – and it’s monitor-less twin, the 6200 – comparable to a 66 MHz Power Mac 6100. To save money, Apple...
lowendmac.com lowendmac.com
lowendmac.com

Performa and Power Mac x200 Issues - Low End Mac

This information is about what are commonly referred to as the x200 series of Performas and Power Macs. These machines, with the exception of the Performa 6360, were all PowerPC 603 or 603e machines with severe hardware problems. The afflicted series includes the 5200, 5260, 6200, 6300, and...
lowendmac.com lowendmac.com


Posted by: aserker on 2025-06-09 06:26:25
Hello,

Any progress in your project?

I'm curious because I would like to do pretty much the same.

I was donated the motherboard of a Performa 5200 and its PSU.
The motherboard is clean with the ROM and the RAM present. Maybe I will have to recap it.
However everything else is missing: no casing, no CRT and no cables at all.
It means I cannot connect the PSU to the motherboard as of now.

Do you have any suggestion on how to connect an ATX ?
Yes!

So this thread here is really me wanting to fix my performa to run with the CRT, but I don't know how to power the analog board with an ATX - if at all possible. And frankly, I'm a bit worried about repairing a PSU (electrical shock, fire, etc). Would love to get the CRT back... and a way to run it with a new PSU but without a working PSU I cannot measure what the analog board needs... hoping someone will figure that out one day.

But what you want to do is just get it to run with an ATX without the CRT. I did that, check this one. I can confirm that all the parts I got works. I did not get the soft boot to work but I was fine with the ATX switch on/off so did not bother much about it.


Your main problem will be how to connect it without having the harness and without having the mirror cable.

Your options for the harness:
- buy one second hand (in theory a harness for 5200/6200/5300/630 should work, I did mine with the harness from 5200)
- solder directly onto the pins on the motherboard (probably not recommended)
- measure the pitch and find a connector that it can slot into that you can solder to, it is actually two pitches one finer ,and one more coarse (only 6 connections)

Your options for video:
- get a mirror-out cable for the 5200 (they are out there but it took a while to find one for me)
- get the card from a 6200 (or 630 - should also work I think) that has the DB15 output, that should take the r,g,b, signals from the motherboard to the card and turn it into DB15 output.
- hardcore: take the r,g,b video signals and figure out how to make a pcb that gives out e.g. vga or mac db15. (I would love to have this as it would make my "slim 5200" more possible, to remove more cables and make it smaller)

Posted by: noglin on 2025-06-09 07:37:01
Nice work !
Thank you for your very detailed answer.

I'm slowly realizing it's quite a challenge with all the missing parts! Thanks again for listing all the alternatives.

Regarding the rgb to VGA adaptator, I know some adapters like this have made for compact Macintosh. I don't how much this could be extended to the Performa.

Posted by: aserker on 2025-06-09 08:07:06