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Looking for ASD 2.5.8

punger

punger

macrumors newbie
Original poster
Feb 10, 2017
9
3
England
Hello, I have a Powermac G5 DP 2.5 and it runs hot (50C Idle, up to 72C at full load). I want to replace the thermal paste to extend the life of the machine but also in hopes of getting the fans to run much slower as the computer is extremely loud most of the time (around 40-50% CPU usage usually kicks the fans to near full speed).

From what I understand if I take the processor cards out which is necessary to replace the paste, the computer will detect a change in hardware and the fans will all run at 100% unless I run the Apple Service Diagnostics disc to calibrate the fans. Problem is there's none on ebay for sale and I can't find any download link at all.

Wondering if anyone here has a link to this software. Some have said you can get the cd by going to an apple store but but it's such an old machine I doubt they would have it, and it'd be a long drive to get to my closest store.
 
AphoticD

AphoticD

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Feb 17, 2017
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The CPU and logic board are paired during the calibration process, so just changing the thermal paste won't cause any kind of hardware level change. In other word, just change the thermal paste and continue to go about your business. The G5 will run cooler and the thermal management will lower the fan speeds automatically. There's no need to run the ASD unless you change the CPUs, or swap them around.
 
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punger

punger

macrumors newbie
Original poster
Feb 10, 2017
9
3
England
I appreciate the help guys, however upon dissembling the system, replacing the paste and re-assembling, the system no longer receives power. No light, no fans, no display when the button is pressed. Not sure if it's worth trying to replace any parts as I'm not even sure where to start with something like this (I've already tried a few things so far).

Thanks for the link/info anyways, will be useful for future systems
 
1042686

1042686

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Sep 3, 2016
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Sounds very similar to what happened to my dual CPU 2.0ghz powermacG5. Internal temperatures were creeping up so I pulled the CPUs and swapped out the thermal paste. When I put her back together, I got nothing - notta. No boot up, no I'm a happy mac chime, no lobo red light - just a big, beautiful aluminum apple brick to look at. Based off the above behavior and asking some of the apple wizards around here, we thought it sounded like a wonky PSU, so I ended up getting a replacement "working used" PSU from ebay and stuck that puppy in there and voila, it booted right up.

What was weird (to me) was that upon inspection of the old psu, I did not see any swelled caps or smokey burnt weirdness as Ive seen in others and when I manually tested the psu by jumping the 20/24 connector, the psu fans spun up, Hah! I chalked it up to a half dead psu (I admit it had been doing weird things for about the prior 3 er 4 months ie: turning off, not turning on right away etc). I salvaged the fans off the back of the unit and dumped the bones. Anyhow, if you can score a cheap PSU for your PMG5 (I lucked out finding a $20.00 unit shipped from Canadia), it could be a fun weekend project and could get you back up and running.

There's the usual stuff to check first - check power connections, re-seat ram in pairs, jump 20/24 pins, reset smu etc. Be sure you are grounded before doing any work. It's just too flippin' easy to kill random stuff in these older computers with ESD (been there done that). and the ensuing PITA migraine figuring stuff out is just not worth it.

Anyhow, best of luck to you. :)
 
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Eriamjh1138@DAN

Eriamjh1138@DAN

macrumors 6502a
Sep 16, 2007
951
1,044
BFE, MI
punger said:
I've come across similar links before but I keep getting "Authentication Required" with a Username and Password input
Click to expand...
Use Firefox to access. Safari didn't as for the username and PW. The dialog that appears also tells you the username and password to use!

If you go up a directory or two, you may see other files worth downloading.
 
AphoticD

AphoticD

macrumors 68020
Feb 17, 2017
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punger said:
I appreciate the help guys, however upon dissembling the system, replacing the paste and re-assembling, the system no longer receives power. No light, no fans, no display when the button is pressed. Not sure if it's worth trying to replace any parts as I'm not even sure where to start with something like this (I've already tried a few things so far).

Thanks for the link/info anyways, will be useful for future systems
Click to expand...

A few things to try;
  • Reseat the CPUs and/or swap them around.
  • Press the PMU/CUDA reset button on the logic board near the lower RAM slots.
  • Remove the PRAM battery and disconnect power, leave it for a few hours and then try again.
On some Macs of this era, a corrupted PMU can cause what appears to be a dead power supply.
 
punger

punger

macrumors newbie
Original poster
Feb 10, 2017
9
3
England
I've checked the RAM, pressed the PMU reset and removed the PRAM, still no luck. I'll try swapping the CPUs around tomorrow when I get some time.

Not sure if it makes any difference, but I still hear the power supply make it's usual noises when the power cord is first plugged in.
 
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1042686

1042686

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punger said:
I've checked the RAM, pressed the PMU reset and removed the PRAM, still no luck. I'll try swapping the CPUs around tomorrow when I get some time.

Not sure if it makes any difference, but I still hear the power supply make it's usual noises when the power cord is first plugged in.
Click to expand...

Hmm, yeah that does. From my limited understanding, effectively if you hear a click when you plug in the power cord, the psu is ok & it’s an issue relative to the lobo. Conversely if you hear no click, it’s a wonky psu.
 
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AphoticD

AphoticD

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Feb 17, 2017
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punger said:
I've checked the RAM, pressed the PMU reset and removed the PRAM, still no luck. I'll try swapping the CPUs around tomorrow when I get some time.

Not sure if it makes any difference, but I still hear the power supply make it's usual noises when the power cord is first plugged in.
Click to expand...

Label your CPUs as “A” (upper) and “B” (lower). Then try in order, testing power on between each step (disconnecting the power cable before each step);

1. Reseat both CPUs in place (A, B)
2. Swap CPUs around (B, A)
3. Remove CPU A (now in lower) to test single CPU B boot
4. Remove CPU B and install CPU A back in the upper slot
5. Reinstall CPU B in lower slot.

If the G5 boots in a config different to A, B, then the fans will run at full speed until you run the ASD calibration process. If your indoor ambient temps are hot, take the G5 outside in the cold with an extension lead to calibrate (or lower the air con temp).

I’ve had my G5 DP fail to boot after working on the CPUs and a reseat or swap has resolved it each time. It’s worth taking a magnifying glass to the CPU sockets to spot any bent pins. If a pin was bent out of place during a reinstall then it will not boot.
 
punger

punger

macrumors newbie
Original poster
Feb 10, 2017
9
3
England
Swapped both processors, tried them individually and put them back to their original configuration, still no power. I also checked the pins on the motherboard and the CPUs and from what I can tell, they look fine, don't see any bent pins. As a last resort I'll see about testing the power supply in the next day or so just in case
 
AphoticD

AphoticD

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Feb 17, 2017
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punger said:
Swapped both processors, tried them individually and put them back to their original configuration, still no power. I also checked the pins on the motherboard and the CPUs and from what I can tell, they look fine, don't see any bent pins. As a last resort I'll see about testing the power supply in the next day or so just in case
Click to expand...

That's a shame. Have a read through the power-on troubleshooting section (page 184) in the G5 service manual here:
http://tim.id.au/laptops/apple/powermac/powermac_g5.pdf

There are also voltage charts on pages 178-182 for the PSU power verification.
 
punger

punger

macrumors newbie
Original poster
Feb 10, 2017
9
3
England
I got it working! I'm to fault as it turns out I was incorrectly re-seating the processors/cooler. The cooler always clicked in one side and around where the processors connect to the motherboard, it felt as if it were fully pushed in while the other side was not fully level but I wasn't able to push it down very far and thought it was meant to just click in one side. I was pretty scared of just trying to brute force it down as most of that side of the cooler seems to get bent pretty easily.

So far though, seems everything is working correctly. Previously, doing very simple things like just opening system settings or a browser would momentarily kick the temps up enough to have the fans on and off in short but loud bursts. Now, it takes a tad bit more for it to reach that noise level. Before I'd idle around 49-52c but it's now sticking in the mid 40s. Before, it was really easy to get the machine above 70c but so far with iTunes and a game running it's not going above 60c. The highest it's gone so far is 62c.

Anyway, thanks everyone for your help, I feel a lot more comfortable working with a G5 now and have learnt a lot!
 
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AphoticD

AphoticD

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Feb 17, 2017
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3,467
punger said:
I got it working! I'm to fault as it turns out I was incorrectly re-seating the processors/cooler. The cooler always clicked in one side and around where the processors connect to the motherboard, it felt as if it were fully pushed in while the other side was not fully level but I wasn't able to push it down very far and thought it was meant to just click in one side. I was pretty scared of just trying to brute force it down as most of that side of the cooler seems to get bent pretty easily.

So far though, seems everything is working correctly. Previously, doing very simple things like just opening system settings or a browser would momentarily kick the temps up enough to have the fans on and off in short but loud bursts. Now, it takes a tad bit more for it to reach that noise level. Before I'd idle around 49-52c but it's now sticking in the mid 40s. Before, it was really easy to get the machine above 70c but so far with iTunes and a game running it's not going above 60c. The highest it's gone so far is 62c.

Anyway, thanks everyone for your help, I feel a lot more comfortable working with a G5 now and have learnt a lot!
Click to expand...

That's great to hear! Well done.

I know what you mean, I can recall the Dual Proc G5 took a bit of force when reseating the CPUs. However IIRC it was the opposite on the Dual Core G5, which refused to click into place until you screw it down.

The CPU mounting system is a bit awkward on the G5s IMO. I'm sure it was intentional to prevent users from working on their own machines. I imagine there are very few G5 owners who have renewed the CPU thermal paste because Apple designed it to be a non-serviceable module. Even throughout the official Service Source PDF I linked to, there is zero mention of renewing the thermal paste. It only mentions to replace "faulty" CPU modules.
 
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1042686

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AphoticD said:
That's great to hear! Well done.

I know what you mean, I can recall the Dual Proc G5 took a bit of force when reseating the CPUs. However IIRC it was the opposite on the Dual Core G5, which refused to click into place until you screw it down.

The CPU mounting system is a bit awkward on the G5s IMO. I'm sure it was intentional to prevent users from working on their own machines. I imagine there are very few G5 owners who have renewed the CPU thermal paste because Apple designed it to be a non-serviceable module. Even throughout the official Service Source PDF I linked to, there is zero mention of renewing the thermal paste. It only mentions to replace "faulty" CPU modules.
Click to expand...

Nice :) the worst parts about working on a g5 for me on both the DP & DC models was of all things that stupid little plastic pin that holds the cpu faceplate on - what a pita to get off without completely scratching everything up. The other was not having a long enough screwdriver for the DC heatsink - had to Gerry-rig two screwdriver extensions together (if that makes any sense) to get far enough down to extract the screws.

Other than that, everything else was pretty straight forward for me ... aside from wanting a Quad that is. Just fueled the fire on that front :D
 
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