PowerMac G5 freezing?

First of all perform PRAM and SMC resets, just in case and then try installation.

It however sounds like motherboard failure. Very common on PowerMac G5's. The problem is usually the chipset/memory controller being disconnected because of a solder failure which occurs after repeated heating and cooling cycles. I think this is the case here. The chipset on these machines run insanely hot during use, if I recall right temperatures were like 70-80 celcius, never seen this kind of temperatures with any PC that I have owned, maybe half of even less of those temps.

What you can also try is to test with known good memory to rule it out, if you have original install disks they have Apple Hardware Test which can be used, but the thing is that in this motherboard failure case it might say that no problems even though there clearly is when operating system cannot be installed or booted.

If it is the motherboard failure, the fix would be to either replace the motherboard or perform reflow/reball of chipset.

 

I had the same issue when i got my PowerMac G5 2.0Ghz from eBay. I tried wiping the hard drive (the previous owner didn't). So anyway
im now at the stage of installing the Mac OS X disk into the computer and shortly after clicking install software, my machine also turns into an Airbus A380, turning the fans up to maximum speed.
I resolved this issue by doing this operation a few times, and if the computer did go into complete meltdown, i would hold down the power button on the front for a few seconds and force kill the machine. Before you try and wipe the HDD though, i recommend making a backup of the software, just incase the computer doesn't like the disks.

im_the_guy

 

@im_the_guy Can you try downloading, burning and running ASD?

If I recall correctly, ASD v2.5.8 was for G5s prior to the late 2005 model and then v2.6.3 was for that last rev.

I have a first gen G5 (dual 1.8ghz) which has been a bit flaky with random intermittent crashes occurring every few weeks. ASD determined one of the RAM chips on the outer set had failed testing, so I tried other DIMMs I had and it continued to fail. I ultimately just removed RAM from these slots and it passed testing with flying colors and has been solid since.

 

I did do a check of my machine (by holding down the 'd' key right after clicking the on button) and my machine was fine, all ram working and motherboard fine.

 

I didn’t realize the G5 had a built in diagnostics mode. I haven’t heard of this before. It would be worth trying the Apple Service Diagnostics (ASD) as it is possibly the most comprehensive test.

 

Are you aware this thread is five years old?

 

I didn't run an ASD on my PM G5. By holding down the 'd' key right after turning on the computer, you launch your machine into basically a recovery mode. From there, you can run an AHT (Apple Hardware Test) which was the one I ran.

 

Isn't that Intel machines only? Certainly doesn't work on my PMG5.

 

I'm not sure why??

 

http://www.techradar.com/how-to/com...boot-options-to-troubleshoot-your-mac-1305645

 

Same here. I tried holding 'd' on 3 different G5s and it did nothing. @im_the_guy Are you sure it's a G5 and not a Mac Pro? Either way, it doesn't resolve the issue, but may help you to diagnose.