macrumors newbie
Original poster
Nov 16, 2011
Sorry, I'm kind of a newbie at this, but I really need some help with my computer!

What's Wrong With My Mac Pro?
My computer is a Mac Pro G5, It's an early 2005, Power Mac with a 400 GB hdd and 4 GBs of RAM.

A few weeks ago it stopped starting up, and it wouldn't start up for several days. I was thinking that it was the hardrive because all the computer would do is idle with the fans going on high speed. So I got a 2 TB hardrive and installed it. We realized that the original 400 GB hardrive plug-in was damaged (not the contactors, but the plastic piece just next to them that helps hold the contactors together.) We repaired it when we installed the 2 TB alongside it and it worked for a while with the 2 TB being the master drive and the 400 GB as a slave/back-up harddrive. (The harddrives were purchased from Apple). Sometimes while we used it, it froze once in a while and we had to shut it down totally.

After a few days, the computer cratered again - only this time the monitor wouldn't boot up. It was receiving power but it wasn't getting a signal.

We opened it up and reset the PMU (It's an older model, no SMU), but it made no difference and then the white light next to the power button wouldn't turn on. It just sits and idles as much as it did before we replaced the harddrive.

We also tried to reset the PRAM, but the computer didn't make the trademark "apple" sound.

A few hours ago I was sitting next to it and I decided to give a chance for a miracle and pressed the power button; it started booting up and did the trademark "apple" sound, but still the monitor is not receiving signal. The white light next to the power button is on now.

I've also noticed that the DVD Drive will not open.

The computer does not always make the "apple" sound when it turns on. Sometimes it just idles.

It can't possibly be the power supply because it exhibited the very same behavior only weeks ago and suddenly began working after we replaced the harddrive only to relapse, though something like that may make sense since it is now running an extra piece of hardware that was not in existence back when it was manufactured.

My new guess is that the graphics card has failed. I pulled it out and took a look at it (I know that just looking at it isn't the greatest troubleshooting method but I have no other method to test if the graphics card is dead or not).

Still there's the fact that the computer has been very unstable in the last week.

Does anyone have any idea what is up with this computer? Is there any other way to troubleshoot/treat the problem? I've already dumped $200 into this computer with no results and I have no idea what else to do. I'd hate to lose my Mac Pro.


macrumors 65816
Sep 30, 2009
I once had an iMac power supply die similarly. It was just being weird- turning off randomly, not starting up, then it would work suddenly.


macrumors 604
Aug 5, 2010
The G5 is not a mac pro :). There are a number of differences. It's just the outside case that is the same. Early 2005 would have been one of the last of the PCI-X generation. It could be a number of things, but that computer is getting to be quite old, and anything you buy for it at full retail pricing will never be recouped. Those sell for probably $300-500 today if they're working. No newer software runs on them. Nothing past Leopard runs on them (and Tiger runs better).

Is a new computer not an option? 2TB drives according to the forums seem to work okay in a G5 but that is the largest they can use.

That should work for getting the drive open, but obviously you wouldn't see it if the display isn't receiving a signal. The point of this is I'd like to know if it will boot from the original installation/utility disk. You can run a hardware check from there. You may want to consider starting to look at newer computers soon.


macrumors member
Mar 7, 2009
Doesn't sound like the graphics card where you mention other things, like the optical disc drive and the sound, are similarly nonoperational. It sounds like the power supply to me. Those tend to sputter out before they die completely and can exhibit some odd behavior before they go. The items you mention could be consistent with that.

I've only ever worked on custom built PCs, does the G5 take a special power supply? If so, one should be a bit cheaper than the hard drive right now as those were not affected by the floods in Thailand.

For future reference, OSX will show a question mark on the screen at boot if it is the hard drive failure.


macrumors 601
May 30, 2006
The easiest way to get it troubleshooted is to bring it in to Apple.

They have the capabilities and environment to fully test the hardware.

A replacement might be in order though, even the Mac Mini is vastly superior to the PowerMac G5 2005 model.
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