Defective Tower of Power.

[iMac600]

It's become somewhat of a tradition that I name my conquest threads anything but the thing i've actually acquired. This one is no exception.

In a nutshell, i've come across a Power Macintosh G5. Single Processor 1.6GHz. 1GB RAM. No Drives. Free, because it doesn't start. When I hit the button on the front the machine powers up just fine, but never completes the POST. Instead the LED on the front flashes three times in a never ending loop. If I reseat the memory on the inner slots, sometimes I can get a successful chime and the machine will run. However it's only a short span of time before the machine reverts to its non-functioning state.

I'm suspecting at this stage that one of the inner memory slots has a bad solder joint. It was a common issue with the early G5s (RoHS strikes again) but one that shouldn't be difficult to fix if my diagnosis is correct. A reflow job will be in order once I receive the necessary tools. Powerbook Medic has replacement G5 Logic Boards for $89 USD at the moment, so even in the worst case scenario I can't see it being difficult to make this G5 run again should I choose to take that path.

The Power Mac G5 has been a collectors target that i've had for quite a while, regardless of its Single Processor base-model status, so I don't intend to let this one slip without a fight.



In addition i've also picked up an LG Flatron 17" LCD display. It only has a VGA input and it is missing its stand, but it is a working display with a maximum resolution of 1280x1024 and certainly nothing to be scoffed at. I've been running it continuously for the last 8 hours without fault. Nice display for testing and running some older hardware, and it means I can finally retire my last CRT.



The image sucks, I know. There's only so many ways to photograph a flat black panel and have it look interesting.

The fun now begins in resurrecting the G5. We'll see how this plays out.

Cheers,

- M.

 

[iMac600]

Less than an hour later and I already have my first update.



It's a bad solder joint. Applying heat to the memory slots allowed the system to boot up successfully.

Looks like i'll be prepping this machine for a reflow job soon. For now i'm celebrating the fact that the machine is easily repairable.

I'm taking a guess and saying the graphics card is the GeForce FX5200 Ultra. I'll have to verify this when I can get the machine to boot.

 

[macman142]

Nice pickup really. I like the single 1.6 G5. As it was the first G5 tower it has some level of interest to a collector.

I have one in my collection. It's not particularly useful as it is huge, not as exciting as a MDD G4 and uses a fair amount of power. But I still like it.

Hope you can get yours repaired/stable.

 

[BGoins12]

Nice find for free. I like the G5s, but they are too power hungry. Plus my Dual 1.25 MDD does just fine for daily use. The only bad thing about the single 1.6 G5 is that they are painfully slow...my aunt has one with 4 gigs of RAM, and my Dual 1.25 outperforms it.

 

[ClassicHasClass]

Maybe it's a relative thing. My quad gulps down (at Highest) about 220W -- on power savings, it's around 170W. Compared to my POWER6 server at 300W+, that's a bargain.

(yes, I know)

 

[Trash80toHP_Mini]

Nice job of troubleshooting a very nice DOA freeb! :approve:

 

[bibilit]

Nice Imac G4 in the background

 

[coius]

is the board in that a DP-capable board where they only put a single 1.6Ghz in it, or can you swap in DP 1.8Ghz/2.0Ghz and run the adjustment program?

It would seem silly and downright unprofitable to make a seperate run for a single CPU board.

 

[coius]

btw if that machine goes south, pop a full ATX board with 6/8 cores, 12GB DDR3 RAM, a few CrossFire/SLI video cards and modify the back and go whoop up on some friends with games

Speaking of which, the first of my parts for my new build comes tomorrow. 3 whole components. Quad Core AMD FX-4100 w/ 8MB L3 Cache, 8GB DDR3-1333 RAM and a CrossFireX Capable board with UEFI, support for 8 core CPUs, 2 PCI-E 16-lane, 2 PCI-E 4-lane, 2 PCI, well you get the drift. Can't wait!

 

[iMac600]

Nice Imac G4 in the background

That's the G4/700, lovingly restored, not a speck of dust internally when I opened it last. Running Mac OS 9.2 and 10.3.5. I managed to acquire a set of Apple Pro Speakers to go with it just a few days ago but forgot to mention them in the thread.

is the board in that a DP-capable board where they only put a single 1.6Ghz in it, or can you swap in DP 1.8Ghz/2.0Ghz and run the adjustment program? It would seem silly and downright unprofitable to make a seperate run for a single CPU board.

It's the same logic board, but without the second CPU board connector soldered in. I suspect there may be some other changes as well, notably lack of supporting hardware for Dual Processors and a slightly slower system bus.

I've seen some impressive PC installations in Power Mac cases. If I ever took that route it would have to be an impressive install, fast hardware and water pump assemblies to cool the lot. Stealth installs are mandatory, the light and fury would have to be visible only when the computer is opened. Tempting, but my priority is still repairing the stock board for now.

 

[LCGuy]

I second that - if you can get the machine back up in action, definitely DO it. While the G5 is a beautifully designed case, its not a terribly good candidate for a PC case, given that you'll have to modify it a fair bit to take an ATX board, and it doesn't have many drive bays, despite its size.

 

[iMac600]

I've been working on this for hours, logic board in and out of the case, reflowed the slots, surrounding ICs and the G5 System Controller ASIC. I just can not make this computer run.

I'm just about to concede defeat to the faulty logic board. Short of a replacement board I don't think it'll run again.

The Power Supply is good, as is the graphics card, memory, processor, drives, all the fans and sensors... so it's worth something I suppose. I'm not sure i'm prepared to cough up the $120 or so for a replacement board from Powerbook Medic, but it may be the only option if the system is to be repaired.

EDIT: As soon as I finished typing out this post, the computer chimed and started up. I haven't a clue what this machine is doing.

EDIT2: It's the G5 System Controller ASIC. If I apply pressure to the underside of the board directly below that chip, the computer will start up every single time. I'll keep the 68kMLA informed of any further developments. For those that aren't aware and would like an explaination as to what i'm referring to when I say the G5 System Controller ASIC, i'll turn over to Steve Jobs.

http://www.youtube.com/watch?v=ve3O6VtBmdc - Skip to 8:20.

 

[iMac600]

Bah, the logic board's warped. Didn't spot it at first, but it became clear as day while i was attaching the G5 System Controller heatsink.

Parts are going away for now. Not sure if i'll end up repairing it.

 

[iMac600]

Well, just to add an outcome to this thread, the G5 will most likely be parted out. I need the money from the components and can probably come across another G5 later on if i'm really set on it.

 

[techknight]

or you could send me the logic board, and i could run it on the IR reflow station and see where that goes. thats how i fixed my imac g5 17". Only thing though is your in Australia so shipping could be a problem.

grab some chipquik SMD291 flux, go around the IC. before preheating.

Really all you need is a pancake griddle setup to about 400deg.

Let it preheat. Then you reflow it with a heatgun. use a cheap thermocouple meter and slowly heat the chip up to 212deg C. then let it all cool down. that should take care of it. Make sure you clamp the board though so it cannot warp during reflow. itll strengthen itself out that way during preheating. Because if it warps during reflow, itll cause bridges around the edge of the IC

 

[iMac600]

or you could send me the logic board, and i could run it on the IR reflow station and see where that goes. thats how i fixed my imac g5 17". Only thing though is your in Australia so shipping could be a problem.

It's already warped, so i'm not really concerned about this machine anymore.