The Power Mac G4 Cube is a very unique Apple computer, with its special and compact desktop (for the time at least) "cube" form factor. It features easy access to its internal components for (some) upgrades, but mostly, this accessibility is used to show off to your friends and family. Unfortunately, it ended up being a commercial failure due to lack of specific market focus and higher price compared to other Apple products of its time with similar or higher specs. Thus, it had a very short life span, being produced only between July 2000 and July 2001 what today lead to a somewhat rare and collectible Mac.
The Cube, like most Apple products, is a solid machine and if you are lucky enough to find a reasonably priced one, most units tend to be working to this day. Among the non-working ones available, chances are that it's because of its power supply (PSU) being dead. Sadly, the Cube PSU is custom made for the Cube, using a proprietary connector cable - making it very rare / expensive to find a plug and play replacement.
Thankfully, you are lucky enough to come across this article! :)
If you have a Cube with a dead PSU, you can use this tutorial to replace it by a modern PSU preserving the original cable, power connector and overall OEM case of the original Apple made PSU.
First, you will need to open the OEM PSU to remove (unsolder) the original cable and power connector plate. I used this guide (from iFixit user Darie H.) to open the OEM Apple PSU. Be patient as it is not easy to get to internals of the original PSU.
Once you open the original PSU, you will be able to desolder both side plates: one with the connector and one with the power plug:
With the original cable in hands, connect it to a bench PSU adjusted to 28V DC to test the Cube and ensure it works. Here is the pinout for the power cable: (A and B are +28VDC, C and D are the negative of the +28VDC and the outer shell is ground):
Note that in my test above, the Cube is also powering the Apple Studio Display through the ADC connector. I wanted to check the current drawn with the display connected and without to order an appropriate 28VDC power supply.
Somewhat unrelated question - what's up with the white supports in the corners inside the clear case?ReplyDelete
The white supports are actually supporting the heavy Cube on the table instead of stressing the fragile policarbonate. These supports should help to prevent the typical hairline cracks on the Cube's acrylic case. Here is a link for these supports: https://www.thingiverse.com/thing:2297009ReplyDelete
Nice work! Im thinking about doing something like this cause im running my g4 cube as a nas 24/7 (with 2 ssds in it). The original power supply is terrible (in terms of efficiency) so thats why it would be well worthed for me to do this.ReplyDelete
Also this project is kinda scarry. (Its not so much about doing someting wrong its more like that I dont really want to leave the house leaving something like that pluged into my wall unattended)
"making it very rare / expensive to find a plug and play replacement"
So you found plug and play replacments? :) Would you be able to link them please <3
This is what I found after researching the entire internet: (power supply)
It has perfect wattage etc.
Together with this adapter:
IDK if it would work though! (Dont know if the adapter would do the right job)
I would really appreciate if you could please let me know what you think about it.
Hello memorian, what I meant when I said "plug and play replacement" was buying a used or NOS original OEM Apple PSU adapter for the Cube (on ebay for example). They show up from time to time, but it is going to be costly and no guarantees on how long they would last.Delete
The 28V DC power supply you recommended should work. As for the plug you linked, I don't think this is the right plug. From what I researched, the Cube power plug is called PDP-40, where the pair of positive pins have bigger diameter than the negative pins. You can find the plug spec here: https://www.cuidevices.com/product/resource/pdp-40.pdf
Hello, very good job. I have done all the steps that you explain in this guide and I have managed to recover my computer. Thank you very much for your support. A greeting from Spain.ReplyDelete
That is great to hear, Bypass! I'm glad your G4 Cube is alive again:)Delete