PowerMac G5 Quad RAM Fix (fans on full blast, won’t boot)

(Sorry for the long title, trying to make it descriptive to help future searchers on this topic.)

Background: I’ve been having problems with the RAM in my PowerMac G5 Quad pretty much ever since I got it:

The symptoms are generally the same. The machine starts to boot, the screen stays black, and the fans come on full blast. Last night I experienced this again.

I’d just put in new RAM earlier in the week and I noticed something a little odd on the first boot after adding the RAM in. Before going to the gray Apple screen, I got the little “folder with a question mark” briefly, then on to the gray Apple screen. It seemed like it was recognizing the new RAM, then going on and booting up.

On a hunch this morning, I removed only half of the RAM I’d installed and tried again. Sure enough, I saw the same little “folder with a question mark” briefly, then on to the gray Apple screen and a successful boot.

Now that I had a pattern, I thought the OWC tech guys might know what was going on. Sure enough, I gave them a call and explained the situation to Andy. As I’ve come to expect from OWC, he listened patiently as I explained the situation, asked a few questions and had a potential solution for me: reset the NVRAM (non volitile RAM).

Note: be sure to have all of your RAM installed before you do this.

Here is how to do it (from OWC):

To boot into Open Firmware, shut down your Mac, then start it up while holding down the Command, Option, O and F keys. At the prompt, enter the following commands (you may want to write them down on a piece of paper before beginning this process), pressing the return key after each:


After which your Mac will restart.

After doing this, the Mac started right up. No “folder with a question mark”, no tornado effect from the fans, just a happy boot.

I hope, hope, hope this solves my RAM problems going forward.

UPDATE: Another tip I received was to unplug FireWire devices before running security updates, etc.