![atx power supply for mac g4 mdd atx power supply for mac g4 mdd](http://atxg4.com/images/MDD.jpg)
if you don't wanna void the warranty of the new power supply, buy an adapter for 20->24 pin ATX and tinker with that to match the pinout. What ponders me though is that the integrated fuse will not blow, though it is rated much less than the breaker.īe careful when using a new atx power supply! the connector will fit but the pinouts are different and you my end up frying either your logic board or the new power supply. I tried analysing the defective psu but neither rectifier, capacitor or anything else on the primary seems broken, the breaker kicks out as soon as i connect it to my wall outlet. Let us know if it does.I also happen to have a 1.25GHz MDD with a failed PSU and i am now using the atx psu of a broken Maxdata desktop PC. Try that combination: between Power On and Ground or between the +25 V Standby and Ground. What I simply did was measure the voltage with a multimeter between, if I recall correctly, were Pins 11 and 12. With this quick solution I was able to bring my Mac back to life three times using that last trick. I am not sure why it worked, but it did after I was unable to power-up my Mac. My Mac powered on flawlessly, even the date and time settings were preserved. Since I was getting the right voltages I put everything back together and then. Here's a good resource from forum member JapaMac. I googled the pin out and then I checked the voltage. The next step was to test the output voltage, so I figured I'll check it at the terminal where it connects to the logic board.
![atx power supply for mac g4 mdd atx power supply for mac g4 mdd](https://x86.co.kr/files/attach/images/1409324/226/659/002/9df603e3f3c90b203c1c623e358a7667.jpeg)
it turns out the fuse is a built-in 250 V - 8 amp ceramic fuse and proximal to where the power cord enters the PSU) and that I could not locate a standard fuse. (I should mention that there were no signs of burnt or exploded circuits, diodes, capacitors etc. Since I didn't know what to look for in the PSU, I closed it back up. My next logical step was to check output voltage. (That whole last part maybe a bit unneccessary, but it sure is fun to do and it brings back memories of how we use to "hotwire" our HMMWVs)Īfter checking with a multimeter, I verified that the PSU was getting the correct input voltage. (it also leaves a nice little nick on the shaft of you screw driver) This short circuit will simply discharge the PSU and you will see a spark or two as the electrical current finds the ground.
#Atx power supply for mac g4 mdd driver
What I did was simply arc the two pieces of metal using a thick screw driver with a rubber grip. That is because the PSU and its capacitors/inductors have electrical charge stored in them. If you happen to accidently touch both pieces at the same time you will receive a nice buzz.
![atx power supply for mac g4 mdd atx power supply for mac g4 mdd](https://i.ebayimg.com/images/g/BjgAAOSwhkdflQF7/s-l400.jpg)
![atx power supply for mac g4 mdd atx power supply for mac g4 mdd](https://medias.audiofanzine.com/images/normal/apple-power-mac-g4-quicksilver-2002-1431090.jpg)
When you open up the PSU you should see something that looks like a cathode terminal, a few inches from this is a heat sink. Additionally I simply stumbled upon this quick solution while I was "poking" around. I am not an expert in electrical engineering so my "solution" may not (or it may) work for your particular case. Since I knew the PSU, was prone to catastrophe I decided to open it up and take a peek. When I tried to turn it back on, it was completely unresponsive. The problem was intermittent and though it was slightly inconvenient I was able to deal with manually updating the date/time settings, etc.Ī few weeks ago, I decided to give the inside of my Mac a quick spring cleaning. I replaced the PRAM battery and reset the PMU. Hello, I just want to share my experiences and solution with fixing my MDD PowerMac power supply.Ī few years back my Mac would reset its clock back to December 31, 1969.Īnd at times it would not power-up unless I switched off/on the power switch on the power strip or unplug/plug the power cable. (the issues regarding these powermacs and the power supply failure is prevalent and much discussion has been made regarding replacing the PSU with a new one or modding an ATX power supply)