Power Mac G5 Troubleshooting

[samusaran240]

So, I picked up a Power Mac G5 a few months ago and now decided to go about getting it cleaned up and check to see if it works. Since I'm posting this, something definitely isn't working. Here's what all I've tried already. I have a G5 1.8 DP (PCI-X) A1047. A late 2003/Original according to Everymac.com

Reset PMU
Replaced Pram Battery with a new one
reseated ram
replaced ram with known good ram from my G4 MDD
Swapped random parts box SSD with a known working one with OS X Tiger from my G4 MDD
Dusted whole system
Repasted CPUs with fresh thermal paste and reseated them

Symptoms
Fans ramp up to 100%
USB Keyboards aren't responding
Sits on grey screen (When SSD with OS is used Otherwise it sits on the no OS screen with the little icon in the middle blinking ?)
Unable to eject disk tray by pressing F12 repeatedly

At this point, I'm not sure what else to try. I'm not an expert when it comes to Mac OS and I definitely don't know much about old Macs, other than their easier to upgrade and repair than all the newer ones.

 

[Bug-Creator]

This might be an issue with SATA1/2/3 not being 100% compatible which would not have been an issue on the G4 with either an adapter or PCI-SATA card.

So...
- remove SSD
- hold "cmd-opt-o-f" on power to see if you get into OF
- type printenv and write down everything with "boot"
- try the SSD on the other SATA port (this can make a difference even if it shouldn't)
- try booting from DVD
- try with a spinning HD as these are far more compatible

Depending on results you have to different routes.

You might also want to make sure the KBD is directly plugged into the G5 and if it ain't a Apple one try another one (USB is was and always will be utter garbage that only works by accident, never by design).

 

[samusaran240]

Makes sense. I used a IDE to Sata adapter to connect the SSD to my G4.

I removed the SSD and tried a hard drive but no dice. I also tried with no drives to see what would happen but the same thing persists. Fans ramp to 100% and keyboard is unresponsive. The little mac computer pops up and alternates between face and ? since there's no OS. I did try to hold "cmd-opt-o-f" but no dice. :c Could one of the CPU's be faulty? Good enough to pass POST but causes an error? I know this can happen with regular PCs so maybe, this could also be true with the G5? I just don't want to think its the logic board.

 

[Bug-Creator]

Sounds more like an USB issue.

Try a known working KBD on all ports.
Try other key combos to see if you get any reaction.

 

[DeltaMac]

"Fans ramp up to 100%"... you should try booting to the Apple Service Diagnostics. That is a downloadable disk image that is used to create a bootable CD, where you can run the Thermal Calibration process. You will need to find the Apple Service Diagnostic (ASD) version 2.5.8.
If you inadvertantly swap the CPUs, that calibration needs to run, and (assuming that's the reason), after the calibration process, the fans will be under control.

 

[Bug-Creator]

Fans ramping up on a non boot is normal. So he needs to figure out why the G5 doesn’t detect SATA devices and won’t react on his KBD.

 

[samusaran240]

What up, its yo boi, back at it again. Sorry for the sudden lack in responses, my boot SSD decided it no longer wanted to be part of my computer and committed sudoku. Fortunately, I keep a image of my boot drive on my NAS that's updated monthly so I really didn't lose any important data. I got a new drive yesterday and rebuilt my boot drive from last month's image.

As for the situation with the G5, I managed to dig up an official mac keyboard that I had back when I used a eMac during high school. Surprisingly, that keyboard actually works. I know this because I eventually was able to open the disk drive. That said, I put in a OS X tiger CD into the drive and tried to boot to it but nothing happened. I pulled the drive out and replaced it with the one from the eMac, which turns out to also not work. I pulled another IDE drive from some old HP server that happened to be old enough to have a IDE drive with a longer IDE cable so I can connect it to the G5. I had no idea if it'd work and figured it'd be worth trying since it'd save me the cost and time to order a replacement official super drive or compatible replacement. Fortunately, this drive did infact work and did try to boot the OS X Tiger disc but it kinda got stuck mid-boot.

As per DeltaMac's suggestion to run ASD, I downloaded the image and transferred it over to my Powerbook G4 and burned it onto a cd. The G5 did boot the disk. I clicked on thermal calibration and it said that calibration was required. I ran it and it says CPU0 Error - CPU intake fan speed error. Check that inner door is inplace and then rerun calibration.

I don't know if the G5 has a sensor that can detect that I have the side panel off of the case but I'm going to go ahead and get the replacement drive installed properly and get the case all closed up then rerun the test. I'll report back later today.

 

[DeltaMac]

There's no sensor for the side door, but there is a sensor board that will detect if the clear inner door (Apple calls it an air deflector) is not seated properly.

 

[samusaran240]

There's no sensor for the side door, but there is a sensor board that will detect if the clear inner door (Apple calls it an air deflector) is not seated properly.

After running the thermal calibration, it was successful for both sockets and the fans have quieted down. They're still a bit loud but no louder than the fans on my main desktop when its encoding 1080p videos. Right now, I'm also running a full diagnostic test on the rest of the system just make sure everything else is all good. I fully populated all 8 dimm slots with known good ram just to make sure everything detects properly. Once that's finished, I'm gonna install an OS using a pair of WD Velociraptors, provided they are detected properly. But so far, everything looks good.

I am considering selling this G5 on ebay and trying to pick up one of the Dual Core models with the intention of installing a second dual core CPU card to make a "Quad Core" model since that'd make for the fastest G5, especially since the Dual core models also use DDR2 instead of DDR1 and they have PCIe gpus instead of AGP gpus. But, I'm not sure yet. I need to do more research on whether or not all Dual Core models have a unpopulated second CPU socket or if only the Quad Core model has two CPU sockets. Heck, maybe I could just buy a Dual core. two socket motherboard and upgrade my own G5 myself and pick up a pcie gpu, the cpus, and ram for it. Like I said, gotta do more research.

 

[samusaran240]

According to ASD, the G5 passed all the tests. After it restarted and I put the OS X Tiger install disc in, it was able to boot into the installer. On top of that, its running WAY quieter now. I think its safe to say that the G5 is running as intended now.

 

[Bug-Creator]

I am considering selling this G5 on ebay and trying to pick up one of the Dual Core models with the intention of installing a second dual core CPU card to make a "Quad Core"

Nice idea.

If only the 2nd CPU socket was populated on the single CPU 2 Core G5s.....

Plenty other differences in the boards and PSU (which both seem to have a much higher failure rate with the Quad) to make that a nogo.

Best you could do is installing 1 CPU out of a Quad into a lower 2.0 or 2.3GHz model which will result in a 2.5GHz DualCore running on a 1.25GHz FSB.

 

[samusaran240]

Nice idea.

If only the 2nd CPU socket was populated on the single CPU 2 Core G5s.....

Plenty other differences in the boards and PSU (which both seem to have a much higher failure rate with the Quad) to make that a nogo.

Best you could do is installing 1 CPU out of a Quad into a lower 2.0 or 2.3GHz model which will result in a 2.5GHz DualCore running on a 1.25GHz FSB.

****, maybe I won't then. I wonder why those boards and psus have such a high failure rate. :0

 

[Bug-Creator]

I wonder why those boards and psus have such a high failure rate. :0

Higher thermal load is the most obvious guess.
I have also seen stats that puts a "downgraded" single CPU Quad at a much higher idle power consumption as a single as a 2.0/2.3 even after that has been upgraded to 2.5GHz.

Given that Apple likes to mess with different part sources on products it might also be that those board ended with inferior caps.
Or maybe just some oversights/error on parts of the mobo that just isn't populated for single CPU.

 

[mac57mac57]

I am considering selling this G5 on ebay and trying to pick up one of the Dual Core models with the intention of installing a second dual core CPU card to make a "Quad Core" model since that'd make for the fastest G5

If you want four cores, you will need to get a G5 Quad unfortunately. If you try adding an extra CPU card to a G5 Dual, you will have a cooling problem. The heat sink of the Duals takes up nearly the whole space available; you could not install a heat sink for your second CPU card.

Alternately, you could convert the whole thing to modern air cooling, where coolers of a smaller size perform better than those that Apple provided with the product. Because they are smaller, you can get two of them into the case.

My advice: if you buy a Quad, be careful of what you buy. Most older Quads have serious cooling issues - their liquid cooling systems are long past their "best before date". The crippled cooling causes the fans to try to compensate, and like yours originally, they end up running at 100%, creating an unbearable amount of noise (if the machine runs at all!).

So, ask for CPU temperature and fan speed readings from iStat Menus or XRG (if the machine has Leopard - XRG is Leopard only) and only buy if CPU temps are in the 40s C or lower, and the CPU intake and exhaust fans are at below 1500 RPM. Anything higher than this suggests a failing cooling system.

 

[Doq]

If you want four cores, you will need to get a G5 Quad unfortunately. If you try adding an extra CPU card to a G5 Dual, you will have a cooling problem. The heat sink of the Duals takes up nearly the whole space available; you could not install a heat sink for your second CPU card.

Alternately, you could convert the whole thing to modern air cooling, where coolers of a smaller size perform better than those that Apple provided with the product. Because they are smaller, you can get two of them into the case.

Even if you could get around that (by, say, cooler modding it), it's just not possible because the logic boards on the Dual Core machines don't have any components populated for CPU B (including the socket itself!!).

 

[mac57mac57]

Excellent point, @Doq!