Mac G5 Failure - could it be the fans?

I have a failing Mac G5 tower (dual 2ghz with 1gb of RAM - from 2004 - with two internal Maxtor drives - startup is 160gb the second is 250gb - running 10.4.11). I took it in for a diagnostic and was told that that 'drive fails verification', 'unit has software corruption' and also that the 'unit passes all testing'. The shop's diagnosis was that what needed to happen was to replace the hard drive (which I decided to do myself).

I just bought a new 500gb SATA which I installed (I removed the other two drives so it is the only drive currently in the machine) - it has a bootable version of 10.4 on it - which was tested and worked on a computer at the store where I bought the drive.

But, the machine still won't boot and is exhibiting the same issues. My computer freezes on the gray Apple or goes to the 'stop' sign thing. I have tried a couple other booting tricks - and once it just immediately turned off and the last time I got a kernal panic.

Is it possible that there is a problem with the fans and that this is keeping the machine from starting up? The day the computer originally crashed it was around 100 degrees...

Is this a road I should go down? Are the fans easily replaced? Wouldn't the Mac store's diagnostic have detected this if it was the problem (I think they ran ASD v. 2.5.8 on it)?

Thanks for any thoughts or ideas!

I don't know which fans you're referring to, however, you should be able to tell if the fans are working by removing the tower case cover(s) and observe them.

Also, I don't believe the fans have anything to do with your machine not booting. You mentioned that the new 500 GB SATA hard drive was able to boot a computer in the store. How did you put Tiger on the new hard drive if your machine was not working?

Actually, your post is a bit confusing. What symptoms was the machine displaying before you replaced both drives with the one? Not booting? Freezing? Kernel panic?

Regards.

All of the symptoms you mentioned were happening before I took my machine in for a diagnostic - not booting (freezing on the gray Apple), kernel panics, would not boot in safe mode. I was able to access the drives via the T key through my MacBook Pro - and the disk utility I ran made some minor repairs but said everything was OK.

The optical drive in my machine is also on the fritz so the nice people at the store where I bought the new internal drive installed a version of Tiger and tested it for me (only because they were out of internal IDE DVD drives - which I would have bought - since I do own a 10.4 install disk - but I cannot test a boot from it since my DVD drive is down).

I guess I don't know which way to go at this point - I have a machine that won't boot and a professional diagnostic that says to replace the drive - which I have done - and it still won't work. I had read an earlier post that suggested that fan problems might be an issue in a machine not booting- so I am just making wild assumptions since I am at a loss.

At this point it's hard to tell just what's going on. The drive is probably OK since you can access it via Target Disk Mode from your MBP. The only thing about Target Disk Mode is it can't tell us if your G5 logic board or graphics card are functioning properly or at all.

From your description of what happened before you swapped out the drive and what's happening now indicates possible trouble with either the logic board or maybe the graphics card. Do you have a spare graphics card you could swap in the machine? I know the G5 machines were prone to overheating - especially the dual models but as I stated in my first reply, you can check that easy enough by removing the panels.

Also, it's probably not wise to spend too much money on trying to repair that machine as it will wind up costing you much more than it's worth.

Let us know.

Regards.

Thanks for the thoughts - my feeling is that the problem is bigger than the drive - and that the logic board might be the issue. I was just encouraged by the Mac store's diagnosis that the problem was with the drive. I thought it would be worthwhile to keep this guy going if I could fix it with an $80 drive.

I don't have a spare graphics card to try but I am considering taking it in to a different shop to get a second opinion. I guess I am just confused why the diagnostic that was run - by a certified Mac repair shop - would not have picked up on graphics card or logic board problems. The notes they gave me claimed they ran the test for 36 hours...

Anyway, it is time for a new machine - I was just hoping to hold off the purchase for a few more months...

lucylittles said:

Thanks for any thoughts or ideas!

Click to expand...

Here's some thoughts (maybe long shots) but just in case:

- Can we assume that you replaced the clear plastic air diverting panel...before replacing the aluminum side panel on your Powermac G5? Sounds strange...but it has happened before.

- Did you install any new ram recently? With only 1gig in it...I'm assuming not...but ya never know.

- Have you tried removing all ram...and then reinserting it? Maybe the ram for some reason got dislodged.

- If the ram is 2 x 512meg sticks...maybe try removing one of the 512meg sticks...and try to boot the computer. If that doesn't work, remove the 512 ram stick that's in the computer, and install the other one...then try to boot the computer.

In your initial post you said that when "the shop" ran a diagnostic...the diagnostic said "unit passes all testing". In your 2nd post you said that "the optical drive is on the fritz". If your optical drive is on the fritz...how could the computer have passed all diagnostic testing run at the shop? What I'm trying to say is...if this diagnostic test didn't identify the known bad optical drive as "bad"...then maybe you can't rely on the rest of the diagnostic test results.

Hope this helps,

- Nick

Have to go with pigoo3..bad memory sticks can cause these type problems..next would be video card or other hardware. You should dust out the inside real good. There are several heat sensors that need to be keep clean..look for the one up behind the front grill. The machine may not like the OS installed from another source..get a new DVD drive..just lay it on top and plug it in. $80.00 is to much to pay for a DVD drive.