I recently bought an old G5 Powermac Dual 2.0Ghz along with a 23" Cinema Display. Model is an A1047, EMC 1969, PowerMac 7,2, made June 2003-June 2004; all based on the Serial lookup on everymac:

https://everymac.com/systems/apple/power...

Aftermarket ad-ons, which were already installed:

• There is an aftermarket ATI Radeon 9800Pro 256mb Graphics Card installed. The GPU fan does spin.

• There is 1.5GB of RAM (6x256MB).

• It did NOT come with a hard drive, but I do have 2 working hard drives which I installed to see if I could get it to boot. One with 10.5, and one with 10.0 (although, I realize that everymac says 10.2 is the lowest it came with).

I have done research and haven't been able to find anything based on my specific problem(s):

• First, and this is the weirdest based on not being able to find anything about it….when power it on the LED light turned on as the button is press; however, as soon as I remove my finger the LED turns off - yet the machine is still running. Anytime after removing my finger from the power button (meaning that the LED is off while the machine is on) if I press the button the light will turn on, and as soon as I remove my finger from the button the LED power light turns right back off (but not the machine).

• There is NO chime.

• The fans ARE running.

• If I leave it running for about 1-2 mins the funs begin to spin very fast…it sounds like an aircraft! lol

• There is NO display to the, Cinema display, which DOES work as tested through the ADC to DVI adapter to my other Mac.

• Various, and working, USB keyboards and mice do not work. Caps lock will not light up, and the mice have no optical lighting underneath. Also, the eject button on the keyboard doesn't do anything.

What I have tried, based on other articles:

• Power supply does click when plugged in, read in the Apple manual that good ones often do that.
• Swapping the positions of the CPUs.
• Running only 1 CPU on the #1 (top) CPU slot; tried with both CPUs.
• Reseating the RAM.
• Using different combinations of the RAM (however using the same amounts, same locations on both sides).
• Removing the graphics card to see if the boot up chime will happen (read that can be a way to test if it is bad, when you don’t have an extra GC laying around).
• I was able to use a paperclip to open the DVD drive, and it does closed by itself when you push the tray.
• Replaced the PRAM battery.
• Tried resetting the SMU by pressing the SMU reset button on the logic board.
• Ensured the CPUs were seated correctly.
• Capacitors look good

Note, that in all of the various combinations mentioned, the power LED light does not stay on unless the power button itself is being pressed.

What are some of your thoughts here? I feel that testing the logic board and individual CPUs with ones known to work would be the next best approach; however, before going out and buying anything I thought I would see what others thought!

Hopefully, this can help someone else too!

Thank you for any help you may provide! :)

⟐ Answered September 24, 2025 at 10:36 MST

Thanks.

⟐ Commented July 28, 2025 at 8:59 MST

⟐ Answer accepted October 17, 2024 at 6:47 MST

⟐ Answered December 26, 2023 at 9:53 MST

⟐ Answer accepted September 13, 2023 at 5:50 MST

Power Mac G5 has been sitting on the shelf of a business for at least 3-4 years with no use or ever being powered up. I get it today and power it up but immediately the fans run high and theres no video on the screen. The power light blinks white twice constantly.

I took out all of the ram - same exact thing (and no beeps even).

I take out all the ram and pram battery - no change.

I held the pmu button - no change.

What am I probably looking at? May just need a new pram battery since it was sitting dormant for so long? logic board? psu?

any help is appreciated.

⟐ Commented August 07, 2023 at 10:56 MST

⟐ Answered July 24, 2023 at 15:18 MST

I put in new ram (4GB DDR1) And then nothing. When i press the power button the white led does not stay on (And no blinking) No video, nothing. Putted the old ram back in, same problem. However i do get two sighs from the fans, and they ramp up to max after approx 10 ~ 15 mins. Also there is a red led right behind the top CPU? (cpu dead?)

Unplugged everything, tried resetting the logic board etc. still nothing.

Any ideas?

Thanks in advance,

⟐ Answered July 24, 2023 at 1:21 MST

But the external Wi-Fi antenna is missing. (It has the Bluetooth antenna.)

Apple part number A1066 (or 603-3420)

I’ve found them used for $30 to over $100, but I’m hoping it’s a standard connector share by other Wi-Fi antennas.

Does anyone know what that connector is called?

The Apple part looks like this:

⟐ Answered May 05, 2023 at 15:33 MST

⟐ Answered October 26, 2022 at 19:12 MST

I have a dual 2.3GHz Power Mac G5 (Early 2005) which has been working fine up until a few days ago:

I was typing something in Microsoft Word (2008) and the mac froze. I tried to boot it up again but it hasn't worked properly since, when you try booting it up it does one of 4 things:

-> Boots normally (but freezes again after ~30 minutes-1 hour)

-> Plays the startup chime but nothing else (no video or hard drive activity)

-> Boots and plays the startup sound but freezes on the grey apple screen (just before the spinning thing appears)

-> Powers on but doesn't play the startup sound.

I tried troubleshooting the RAM but didn't have much luck. When the Mac is running it shows the proper Dual 2.3GHz PowerPC G5 CPU and 2.75GB of RAM (4x 512MB sticks, 2x 256MB sticks and 2x 128MB ones) on the 'About this Mac' screen. I've also tried resetting PMU etc. but there doesn't seem to be any correlation between what I do and what the Mac does, it just does whatever it wants.

Yesterday I booted it up again using 2GB (2x 1GB sticks) of RAM that I took from my PC (and know to be working) and it recognised the RAM and worked for about an hour before giving me a Kernel panic reading:

System Failure: cpu=1 code=0000000A (Lock timeout)

Latest crash info for cpu 1:

Exception state (sv=0x3de97280)

I have the whole kernel panic photographed but I don't know how much is important (I can type out the rest if needed).

I realise it's an old Mac but it still works great (or at least up until now) and performs fine for what I need it for so I'd be grateful for any help, thanks :)

⟐ Answered July 11, 2022 at 17:31 MST

If this is normal for this machine or if it might just need a dusting that’s one thing. But I don’t even know where this is located on the board. Any guidance is helpful. I plan on tearing this thing down soon and giving it a through cleaning, but if there’s any places I should focus on I will.

⟐ Answered April 19, 2022 at 10:48 MST

⟐ Answered August 24, 2021 at 11:14 MST

By the way, I was connected to the internet by ethernet.

⟐ Answer edited August 23, 2021 at 23:57 MST

⟐ Answered August 14, 2021 at 5:02 MST

This is what I have tried:

• replace with other RAM
• unplug drives
• Reset nvram like in this article. The problem is then that I have problems getting to OpenFirmware. Sometimes I am able to but when I get to the OF screen there is no reaction from typing. I can i.ex. type the first line but then there is no response from the keyboard. The keyboard is plugged directly into the USB port.

*

I got hold of the Apple Service Source Manual for Quad G5. (Let me know if someone needs that!) and just getting to the cooling and the power supply seems a bit tricky. So I read about this Apple power supply exchange (http://www.apple.com/support/powermac/po...) and am trying for that first. So it seems from the LED light that the CPUs are overheated and that could be related to the power supply going bad. I will post results of my shot at Apple.

• UPDATE - THINK I MAY GIVE UP **

I took the machine to an Apple service center and they confirmed it was the processors gone bad. Of course this has to do with the cooling failed. Still I was not able to get a warranty repair even if I showed them the extended powersupply article and the article about the cooland leak. They said the machine was too old. They did offer me to fix the machine for about $1300. Since this is 2 machines with same error and since I have 16GB of RAM invested in each one just before this all happened, I might just have to accept the offer. Any comments?

⟐ Commented June 14, 2021 at 12:11 MST

Any suggestions?

Still not resolved. The machine is a 2.0GHz dual tower model, late 2005. I can remove the inner cover and the red light goes on. Tried resetting both PRAM and SMU but still no luck. Earlier in the week, I was able to reboot it but if I turned it off, it wouldn't go back on again. Tried new power cable and different outlet but same thing.

Sounds like the power supply. Where can I buy one for this model? Are there any disassembly guides on iFixit to help?

⟐ Commented May 12, 2021 at 6:29 MST

It will run for weeks without problem, and then all of a sudden, it will just power off as if the cord was suddenly pulled out from the wall.

Sometimes, it is necessary to disconnect the power supply in order to reboot, sometimes not.

The /var/log/system.log shows a repeated Fan failure! message (see below for excerpt)

The power supply is usually connected to a power board that protects against surges. I also tried plugging directly into a power point via a standard extension cord - but same problem. I don't use a USP.

I installed temp monitor - it show 'memory controller heat sink' at 65-70C - not sure if that is a problem? Sometimes I have noticed that the CPU A temperate exceeds the 'Upper Limit' of 75

The fans don't seem to be a problem but I am not sure - I checked all the fans by booting up with the cover off, and all seem to be working OK. I guess there are fans in the heat sink which you can't see to determine if working.

I notice that the problem was worse during summer than now at winter, so maybe it is something to do with a thermostat overheating?

I ran the Apple Hardware test (from the CD that come with the MAC) - I initially ran it with the full compliment of memory but found that the fans went into a high rev, and the test (even the Quick Test) wouldn't complete.

So I uninstalled all but the original memory and ran both the Quick Test and the Extended Hardware test - both did not show any issues.

I had two internal hard drives installed - when I removed one of these, the power downs decreased making me think the unit is overheating with the extra drive?.

The Power Mac is under a desk with reasonable circulation around it front and back although it could be better. It was operating fine in the same position for 3 years prior.

Apple reseller says it is the power supply, but I think it is probably something to do with the thermostat closing the machine down.

Have reset the PMU.

Hardware Overview:

Model Name: Power Mac G5

Model Identifier: PowerMac7,3

Processor Name: PowerPC G5 (2.2)

Processor Speed: 2 GHz

Number Of CPUs: 2

L2 Cache (per CPU): 512 KB

/var/log/system.log:

May 22 00:03:05 Fella kernel[0]: Fan failure!

May 22 00:03:35: --- last message repeated 29 times ---

May 22 00:03:35 Fella kernel[0]: Fan failure!

May 22 00:04:05: --- last message repeated 29 times ---

May 22 00:04:05 Fella kernel[0]: Fan failure!

May 22 00:04:35: --- last message repeated 29 times ---

May 22 00:04:35 Fella kernel[0]: Fan failure!

May 22 00:05:05: --- last message repeated 29 times ---

May 22 00:05:05 Fella kernel[0]: Fan failure!

May 22 00:05:29: --- last message repeated 25 times ---

⟐ Commented March 15, 2021 at 10:43 MST