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Lud DiLettante

macrumors regular
Original poster
Dec 17, 2015
149
27
Finland
My G5 dual original 1,8GHz has been dead for some days. (I only have one processor in it... Some months ago I took out one processor in a similar situation, that made the G5 work again, see: https://forums.macrumors.com/threads/g5-black-screen-no-chime-nothing.2022665/ )
To copy from the troubleshooting manual, this is what I have: "Power-on LED illuminates when power button is pressed and fans spin continuously but there is no boot tone or video".
A condensed version of the instructions:
"Reseat video card./Verify speaker cable is fully seated./Reset logic board./Remove/reseat processor(s)./Replace logic board."
But then, the power-on LED flashes 3 times and I'm told this is RAM-related. I still don't understand why this is not in the troubleshooting manual... Neither is the battery.

Anyway, by now I've tried everything in the *manual* except reseating processors. I also took out RAM sticks - first I tried without the outermost of the 4 pairs, then proceeded until I was down to the center pair. After that I removed them and replaced with the ones I took out first. So far, no change. Since I tried *without* each pair, if it was down to the RAM this would mean there'd have to be faulty sticks within more than one pair, right? Is there a simple shuffling guide for how to test 8 sticks..? It's kinda frustrating to go thru them by the time it begins to seem that either several have failed at the same time, or the fault is elsewhere (which I guess by now is pretty obvious).
At the moment I'm also either going to test the battery somewhere or just order a replacement anyway.
So, how is it, do the 3 flashes really rule out *anything*? Could this still be about the processor? I'm beginning to realize losing a logic board is worse (or at least more expensive) than losing processors...
(Would any symptoms have helped with troubleshooting..? All I can remember recently was occasional crackly sound in external speakers and some Webkit crashes.)
 
PS. To my surprise I found the right battery at a local store so I'm going to try that when I get home...
 
I would try reseating the processor. The PRAM battery shouldn’t need to be installed to boot the G5.

I had an ‘03 Dual 1.8 G5 fail in a similar way last year after many years of reliable service (purchased in '04). It got progressively worse until it failed to boot while the graphics card was installed. I tried everything short of oven baking the logic board (I know some have reported success with the technique, but I didn't feel comfortable with it). I eventually conceded defeat and ordered in a replacement board. I spent more time, money and energy on this Mac than I should have, but I really just wanted my old faithful tower back up and running.

The funny thing is now that it all works again, I've hardly used that particular Mac. I do fire it up once every couple of weeks just to keep the PRAM battery charged and in check though.
 
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Ok, it wasn't the battery...
By the way, I realized that when I took out RAM sticks I had forgotten to detach the power cord... So, is this a big risk..?
Tips on shuffling etc still welcome. As if....
 
It's not recommended to have power connected, but from my experience, I've never fried anything by doing that. So long as the Mac is powered off (not running) and you've discharged your own static before touching things, it should be okay.

Another thing to try if the CPU reseat doesn't work, is to remove the current CPU and install the originally removed CPU in that top slot. If that does get the Mac to boot, be sure to run the CPU recalibration service from the ASD CD. Chances are on the G5, the logic board is at fault and both your CPU units and RAM are OK.
[doublepost=1507475657][/doublepost]Given that you're having a similar issue to what I went through (on the same model), can you just try booting with the graphics card removed?

I'd be curious about that AGP related issue, as it could be a weak point on these boards after years of use. Put two sticks of ram back in at the two inner/center slots and boot without the AGP card, listen for a tone. If no tone, try plugging in headphones to the jack on the front panel and power on again. If you get a boot chime and the HDD starts to churn like its booting okay, then your Mac has a failed AGP slot as mine did.
 
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Thanks Aphotic. Maybe tomorrow I'll continue... (and I hate posting from the phone)
[doublepost=1507476576][/doublepost]If AGP is the same as video card then I did that already...
 
I got around to reseating the processors at last. Things slow down once you lose hope... What's removing and reseating a processor supposed to change, anyway..?
I first reseated the upper one that's been the one in use recently. Things were the same as before - 3 flashes.
I then replaced it with the old lower processor that I had considered faulty.
At first, the only difference was that there were no LED flashes... otherwise the same. So there was no chime, but for some reason I decided to plug the monitior in for another try.
Well, this time the 3 flashes were back. But I also got "rev" noises which I guess meant that the fan wasn't seated perfectly since they stopped after reseating the fan.
I unplugged the monitor for a third try. This time, surprise! There was a CHIME! Yes, a boot tone! Something there hadn't been even when I last used this processor. Still 3 flashes tho.
Now, because I got the chime I wanted to try again with monitor. Yes, I got the chime again but still no video. Because of the fan thing & to check the red lights I tried a couple of more times - but I got the chime no more..! The 3 flashes stay, and a red light above the power button (none at the back).
So. do the occasional chimes mean I might still have some hope..? I went to look at the manual at "Power-on LED illuminates when power button is pressed, fans spin, and boot tone chimes, but there is no video" but since now there is no chime again I thought I might stop testing until I've got some answers...
A dumb little question: is the plus end of the battery supposed to be at left or at right? I forgot which way it was before I tried replacing it and nothing I see indicates which way around it goes...
 
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OK, I confirmed the battery position - there's even an Ifixit guide on how to replace it that shows the battery the WRONG WAY round! Luckily people complained so I found out...
 
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All signs point to a dying logic board. It might be time to look for a replacement Board or possibly a replacement Mac.

Here’s a shot of the part I ordered for my 1st gen ‘03 Dual 1.8Ghz G5 in Dec 2016.

The majority of the cost was shipping to Australia, I can’t recall the split exactly, but I think It was about $40 for the board alone. The good thing is it was an exact match of the model number on the failed board, so I was confident it would be compatible.

0490035C-C6D3-448C-B136-17B0E8C5E9B8.jpeg


It wasn’t the most economic (logical?) purchase. I just wanted it working again. Everything clicked back into place and it has been working flawlessly since.

Anyway, I hope that helps you decide which direction to go.
 
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Thanks for everything AD. So it seems even the original problem with the lower processor could've been something about its connection to the logic board as opposed to the processor itself...
So, unless I get a new logic board I'll have to get a computer that's compatible with my hard disks (2 x Seagate 1000GB SATA AF, model STR009, not sure which specifics count), or then use some other compatible computer with which to move my files to a different hard disk...
I already found about another G5 for sale within a couple hours drive from me, so I'll check that...
Thanks again, see you around...
[doublepost=1508251555][/doublepost]I might still try this... https://discussions.apple.com/thread/4298725
[doublepost=1508251828][/doublepost]PS. Oh it doesn't mention it but I do remember reading you're supposed to warm the area at the middle right from the RAM slots, at middle temperature, before booting...
 
Before you take a trip to view the G5, has the seller given you any specifics? If you haven’t done so already, ask for the serial number (label on the bottom pane when the side door is off). With the serial, you can lookup the model details and specs at EveryMac.com using the serial lookup.

Your hard drives will be compatible with any G5 or Mac Pro. With a G5, you can easily pull out the existing drive(s), put yours in and power on.

Unless you are set on a G5 exclusively, a Mac Pro would make a welcome step-up and will cater for 4 SATA drives. A model from 2006 to 2009 would make for an easy, cost effective and mostly more compatible/current option at a very good price. You would add your drives in addition to the existing boot drive(s). All of these models will run Leopard and the ‘06 - ‘07 models can also run their machine specific versions of Tiger if that’s a preference.

Most PowerPC-only software (if you have any) will run seamlessly under 10.4 - 10.6 Snow Leopard via the Rosetta translator.

The only downside of the MP over a G5 is a lack of Classic support (even if you install Tiger), but there are alternatives to emulate Mac OS 9 in a window (or full-screen) with SheepShaver and modern versions of QEMU.

The Mac Pros crunch data much faster, run cooler, quieter and as outlined in this thread, they can be more power efficient (but not always).

I run a series of Macs, including G5s and a 2008 MP (as seen in this thread), which all play their role. If you are looking for one machine to do all you need, it wouldn’t hurt to move up a generation or two.

That was a bit of a tangent sorry, but the MP option is something to keep in mind before driving a few hours to buy another G5, which could have it’s own set of aging problems.
 
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I might still try this... https://discussions.apple.com/thread/4298725
--- Post Merged, Today at 12:50 AM --- PS. Oh it doesn't mention it but I do remember reading you're supposed to warm the area at the middle right from the RAM slots, at middle temperature, before booting...

These are all last leg attempts to flog a dead horse. Some people have also had luck with sticking the logic board in the oven to reflow old solder, but it’s not going to be a reliable fix.
 
Well, what can I say but thanks again AD...
I don't think the seller gave more specifics than G5 Dual 1.8GHz. But I'll check for available Mac Pros too.
I'm curious, what role does your G5 play among the Macs you have..? And what's the role of Classic for you..?
 
Hey, no problem. I feel I complicated things a little though.

My G5(s) are filled with my music production suite; apps, plugins and audio sample libraries. I have two G5s setup near identical, running Leopard with the same full DAW and plugins, then sync them over gigabit ethernet with the Mac Pro (host) for MIDI control from a single NI controller.

I can have one G5 running a stack of audio FX plugins, while the other runs a series of virtual instruments.

My Mac Pro runs rings around both of these G5s, but there are a few specific plugins/instruments which were never ported to Intel (or I chose not to upgrade), so I keep them running on the PowerPC platform.

I also find Aperture 2, Adobe CS3 and Final Cut Studio 2 all run beautifully on the top-end G5 when coupled with a decent graphics card and have kept these software versions a part of my creative workflow.

Secondly, the G5s are in use for software testing as I am in the early stages of developing my own applications and intend to provide Universal support for PowerPC + Intel (Tiger through to High Sierra).

I don't really have a need for Classic. It's purely for nostalgic purposes and for occasionally accessing old documents/projects from before the turn of the century. I have recently obtained a handful of Macs which can actually boot into OS9 (and 8.6), so they will likely replace Tiger's Classic Environment for me when I feel the need to step back in time. Plus Sheepshaver on the Mac Pro works well enough and is fast and easy to launch whenever I want to go back to an ancient version of software like QuarkXpress, Macromedia Director, StrataVision 3D or something.
 
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OK. I did know many people thought the move into Intel was a step back in some way but I never really knew what difference it might make for myself (except for all the hacks I need now..!). But I didn't like the idea of Macs becoming more like Windows computers...
 
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I know what you mean. The Mac Pro can natively boot Windows if you ever feel the need to swing that way.

I did have Windows 10 Pro installed on my Mac Pro via Bootcamp, but found that I just didn't use it. I had it setup solely for my Steam Library which I never seem to have time for anyway. If I do rarely make the time for gaming, I found many of the Steam games I've purchased have Mac ports and some of the Windows only games will even play in Mac OS X using the Windows Steam client under Wine.
 
Have you had the power supply tested? System instability with the machines I work with (Dual processor Lenovo and HP Workstations) is often traced down to power supply modules starting to fail. Starts when they're under load then gets worse and worse...
 
Have you had the power supply tested? System instability with the machines I work with (Dual processor Lenovo and HP Workstations) is often traced down to power supply modules starting to fail. Starts when they're under load then gets worse and worse...

Good thinking. There is a power schematic in the G5 service manual for this model at http://tim.id.au/laptops/apple/powermac/powermac_g5.pdf

Jump to the Power Supply Verification section (Page 178) for pinout diagrams. If you have a multimeter on hand, you can test the lines yourself to confirm.

If you were to pickup the known-working Dual 1.8, the power supply should be interchangeable, although there were a few Dual 1.8Ghz revisions, so make sure the PSUs are a match (My Dual 1.8 used the 604w).

You must be getting good at tearing this monster down. It's quite a job!
 
Have you had the power supply tested? System instability with the machines I work with (Dual processor Lenovo and HP Workstations) is often traced down to power supply modules starting to fail. Starts when they're under load then gets worse and worse...

Nope, and I don't have a multimeter (might be possible to borrow). But then, in the service manual the power supply is only mentioned where the fans don't work, and mine do...
 
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