Hello,
When I connect my PowerMAc 8100 to work with an ATX power supply. It is always on and the hard disk quickly get on the sleep mode. The CPU is getting hot and the monitor doesn't work.
Thank you for your time and interest.
Did you modify that ATX wiring harness/plug to be compatible with an 8100? ATX pinouts don't directly match those of any Apple computer's power supply, even if the connector can be plugged into the motherboard. Some models will run with a modification to the ATX power supply, but the conversion is very model-specific. Connecting a power supply that's not compatible in terms of the voltage at each pin will likely damage the motherboard.
Hello ouzcoskun,
Welcome to Apple Support Communities!
If we understand your post correctly, when you connect your Mac with an ATX power supply it quickly goes to sleep mode and the CPU is getting hot and the monitor doesn't work. We'd like to help!
Let's try an SMC reset.
How to reset the SMC of your Mac
You may also want to try an NVRAM reset.
Reset NVRAM or PRAM on your Mac
We also recommend starting in safe mode. Sometimes just starting in this mode and then restarting can resolve issues like this: How to use safe mode on your Mac
You can also create another user on your Mac and test to see if you experience the same issue.
Set up users, guests, and groups on Mac
You may want to also run Disk Utility which will check for and fix errors related to the formatting and directory structure of a Mac storage device.
Repair a storage device in Disk Utility on Mac
Let us know if you have any questions.
Thank you for using Apple Support Communities.
Take care!
PowerMac8011 with ATX Power Supply problem
