PowerMac G4 MDD GPU Issue?

[asdfguy86]

Hi all!
My PowerMac G4 has been giving me a strange issue lately, and because of what it does I'm going to guess it's the fault of the graphics card.

When I turn it on, it will make the chimes sound, the fans will turn on (not at full speed), the hard drive will start seeking like it normally does, but that's it. No video display signal ever comes in, no matter what.
I have tried re-seating the RAM, swapping out for different RAM, and nothing changes. I have also tried many different monitors, VGA cables, and DVI to VGA adapters. Every time, I get no video signal.

Specs of the PowerMac:
PowerMac G4 MDD
2GB DDR
1.25GHz Single PPC G4
3x HDDs, 160GB Maxtor drive, 250GB Seagate drive, 80GB Hitachi drive
ATi Radeon 9000 PRO Mac Edition
Mac OS X 10.4.11

 

[weckart]

Hold down the Opt key after the chime. Do you get a boot selector screen?

 

[z970]

Take out the graphics card. Take a Q-tip and some rubbing alcohol. Dip the Q-tip in the rubbing alcohol. Run the Q-tip over the GPU's golden contacts, in an outwards motion. Keep doing this for all of the contacts, on both sides. Then, dip the Q-tip again, and turn your MDD over. Squish the soaked Q-tip over the GPU slots, so the rubbing alcohol gets in. Stand it up again, and wait for 5 - 10 minutes, then plug everything back in with a firm connection.

If your card is not b0rked, I guarantee you this will fix it.

 

[asdfguy86]

Hold down the Opt key after the chime. Do you get a boot selector screen?

Well, I just tried doing that and the PSU went BANG, and then smoke came out of it. It smells awful...

Looks like I need a new PSU...I'm amazed it still stayed on after that for the 2 seconds it was still plugged in...

It is (or was) an AcBel 108W power supply. The PSU used to work perfectly fine, but it seems like MDDs have lots of PSU issues anyway, from what I've read
[doublepost=1534785563][/doublepost]

Seems like it took out the graphics card in a way..the Mac also doesn't boot anymore. I'm gonna hope that the PSU just doesn't work, and it didn't take out the whole motherboard with it.

 

[z970]

Well, I just tried doing that and the PSU went BANG, and then smoke came out of it. It smells awful...

Looks like I need a new PSU...I'm amazed it still stayed on after that for the 2 seconds it was still plugged in...

It is (or was) an AcBel 108W power supply. The PSU used to work perfectly fine, but it seems like MDDs have lots of PSU issues anyway, from what I've read
[doublepost=1534785563][/doublepost]

Seems like it took out the graphics card in a way..the Mac also doesn't boot anymore. I'm gonna hope that the PSU just doesn't work, and it didn't take out the whole motherboard with it.

My condolences.

 

[0248294]

Does that coil have any signs of being burnt or blown up, or is it just a chip in the ceramic top? If it's just that, I wouldn't worry about it. From the very blurry photo, it looks like it's fine, as the internal part of the coil looks like it's not damaged.

 

[asdfguy86]

Does that coil have any signs of being burnt or blown up, or is it just a chip in the ceramic top? If it's just that, I wouldn't worry about it. From the very blurry photo, it looks like it's fine, as the internal part of the coil looks like it's not damaged.

That wasn't there before the PSU smoked, but I really don't have a way of telling if the graphics card still works, as the PowerMac doesn't turn on at all anymore.
The only other AGP machine I have is a Pentium 2 PC, so testing a PPC Mac card in a PC is probably out of the question.
[doublepost=1534799758][/doublepost]

My condolences.

R.I.P to this old Mac, I guess. Hopefully I can get another PowerMac for cheap. This PowerMac was a find at an e-waste center, so I guess you get what you pay for (even if it's free)

 

[weckart]

The only other AGP machine I have is a Pentium 2 PC, so testing a PPC Mac card in a PC is probably out of the question.

Well, pop the card in the PC and boot up with a DOS disk with an old copy of atiflash on it and run atiflash -i. If it sees the card and detects the BIOS chip then it probably survived the blast.

 

[asdfguy86]

Well, pop the card in the PC and boot up with a DOS disk with an old copy of atiflash on it and run atiflash -i. If it sees the card and detects the BIOS chip then it probably survived the blast.

I tried that, and it says "adapter not found".
In order to see a display, I hooked up a PCI ATi Rage IIC, and I put the Radeon 9000 PRO Mac Edition in the AGP slot on the PC. Should I try something else? Or is this card a goner?

 

[Raging Dufus]

R.I.P to this old Mac, I guess.

Well, maybe not so fast. If the PSU is dead - which seems likely, but there are ways of finding out for sure - you can fix that by adapting a standard PC ATX power supply to work with your Power Mac.

If you're capable of stripping and splicing together a few wires, even if it's just twisting them together and covering with electrical tape for starters, you can make an adapter like this one. The guy responsible for that page also sometimes sells the adapters through Etsy, though he seems to be out of stock at the moment. He has been known to make special orders on request, so if you want to just buy one it's worth asking him. I've made my own adapter using his instructions, a couple of times; and it's a much better (and cheaper) solution than trying to pick up a used MDD PSU, off eBay or elsewhere, that's bound to fail sooner or later. Plus, you're keeping your grand old machine out of a landfill. Win-win.

Here's a YouTube video that takes a slightly different approach. There are other resources as well, just search a bit and you'll find them.

You'll want an ATX PSU of at least 300W or so, which even new are usually inexpensive. It will be virtually impossible to find one that will fit where the original MDD PSU goes, but that problem too has been solved in a few different ways. In my current setup, I have a 540W ATX PSU installed directly above the optical drive bay, attached to the top (inside) of the MDD's case with velcro. Again, just search a bit and you'll find various solutions, if any of this interests you. Good luck!

 

[swamprock]

Well, maybe not so fast. If the PSU is dead - which seems likely, but there are ways of finding out for sure - you can fix that by adapting a standard PC ATX power supply to work with your Power Mac.

If you're capable of stripping and splicing together a few wires, even if it's just twisting them together and covering with electrical tape for starters, you can make an adapter like this one. The guy responsible for that page also sometimes sells the adapters through Etsy, though he seems to be out of stock at the moment. He has been known to make special orders on request, so if you want to just buy one it's worth asking him. I've made my own adapter using his instructions, a couple of times; and it's a much better (and cheaper) solution than trying to pick up a used MDD PSU, off eBay or elsewhere, that's bound to fail sooner or later. Plus, you're keeping your grand old machine out of a landfill. Win-win.

Here's a YouTube video that takes a slightly different approach. There are other resources as well, just search a bit and you'll find them.

You'll want an ATX PSU of at least 300W or so, which even new are usually inexpensive. It will be virtually impossible to find one that will fit where the original MDD PSU goes, but that problem too has been solved in a few different ways. In my current setup, I have a 540W ATX PSU installed directly above the optical drive bay, attached to the top (inside) of the MDD's case with velcro. Again, just search a bit and you'll find various solutions, if any of this interests you. Good luck!

I did the same as you with my old MDD, except I was sure to run a ground wire from the PS case to the computer case to make sure it was grounded properly. I'm not sure if it's completely necessary, but it couldn't hurt.

 

[Raging Dufus]

I was sure to run a ground wire from the PS case to the computer case to make sure it was grounded properly.

Probably something I should do too, even though I haven't run into any problems. That's a wise precaution that hadn't occurred to me, thanks.

 

[asdfguy86]

Well, maybe not so fast. If the PSU is dead - which seems likely, but there are ways of finding out for sure - you can fix that by adapting a standard PC ATX power supply to work with your Power Mac.
MDD's case with velcro. Again, just search a bit and you'll find various solutions, if any of this interests you. Good luck!

I'll definitely give that a try. I do have a 250 Watt Power supply lying around, but I'm not too sure if that's enough since you recommended 300 Watts. I have heard a bit about converting ATX PSUs to work with the PowerMac, and that's likely what I will end up doing.

Plus, you're keeping your grand old machine out of a landfill. Win-win.

Hah, funny coincidence is that I saved this machine from an e-waste landfill type place. It's always had a fair share of issues though, at first the vents and fans were covered in dust, and it smelled like cigarette smoke. Nonetheless I want to hold on to this machine for as long as I can.

 

[z970]

I'll definitely give that a try. I do have a 250 Watt Power supply lying around, but I'm not too sure if that's enough since you recommended 300 Watts. I have heard a bit about converting ATX PSUs to work with the PowerMac, and that's likely what I will end up doing.

Hah, funny coincidence is that I saved this machine from an e-waste landfill type place. It's always had a fair share of issues though, at first the vents and fans were covered in dust, and it smelled like cigarette smoke. Nonetheless I want to hold on to this machine for as long as I can.

Thank you for your service [to old Macs].

 

[weckart]

I tried that, and it says "adapter not found".
In order to see a display, I hooked up a PCI ATi Rage IIC, and I put the Radeon 9000 PRO Mac Edition in the AGP slot on the PC. Should I try something else? Or is this card a goner?

Sounds like a goner. You could try flashrom -i as well; there's a good chance the BIOS chip is one that flashrom supports but if atiflash isn't picking it up then I wouldn't have much hope.

The only other thing that springs to mind is that the 9000 PRO is one of those ADC cards with a weird pinout that passes DC power through the card to the ADC port. While you can flash a PC card to work in a Mac, the PC might be having issues working out what the Mac card is, so I'm not 100% certain the atiflash test is definitive. TL/DR hold onto the card until you can test it in a suitable Mac.

 

[Raging Dufus]

I do have a 250 Watt Power supply lying around, but I'm not too sure if that's enough since you recommended 300 Watts.

There's nothing wrong with giving the 250W PSU a try, provided that you're only using the standard graphics card, running one hard drive, and don't have a lot of USB/FireWire peripherals hooked up. Think of it (the 250W) as a proof of concept only, though; keep in mind that the original PSU's in MDD's were 360W (at least, in the dual-CPU models, which is all I'm familiar with).

I think you mentioned that your potentially dead one was 108W, which I would look at again if I were you. I don't think that's quite right, because Apple hasn't used a PSU that weak in a Power Mac since before the G3 era. I'm thinking yours, if it's original, must have more wattage than that.

I personally would not go with anything less than 400W for a replacement; but that's me, I have dual processors, and don't have any idea of your particular needs. I think 300W is a reasonable minimum for a single-CPU MDD.

As far as choosing a replacement, it doesn't need to be anything fancy; in fact, you can run into some issues if you try to go with a "green"-type PSU, for instance this one, which I've tried myself and had a hair-pulling time trying to get a Sawtooth G4 to run reliably. I'm thinking the problem there was the "Active PFC" part, explained here, which I think didn't play nice with my Mac's power management. I swapped it out for one like this (no Active PFC), and all the problems disappeared. Keep in mind, those experiences were with a Sawtooth, which is a different animal from your MDD; it's just an example.

Another thing to keep in mind is the orientation of the fan(s) on the ATX PSU. Instead of the ones I linked above, which mounted without issue in a Sawtooth; you may want to choose something with a different intake/exhaust configuration, because your mounting options inside the MDD are limited (if you're not mounting it inside, it won't matter). I chose one like this, because the intake w/fan on bottom (inverted from the way it appears in Amazon's pics), and exhaust out the side, provided better airflow for the way I have it mounted. Just figure out how you want to do it before you buy a PSU.

 

[asdfguy86]

Sounds like a goner. You could try flashrom -i as well; there's a good chance the BIOS chip is one that flashrom supports but if atiflash isn't picking it up then I wouldn't have much hope.

The only other thing that springs to mind is that the 9000 PRO is one of those ADC cards with a weird pinout that passes DC power through the card to the ADC port. While you can flash a PC card to work in a Mac, the PC might be having issues working out what the Mac card is, so I'm not 100% certain the atiflash test is definitive. TL/DR hold onto the card until you can test it in a suitable Mac.

That's very true. It does have one of those ADC connectors on it, and once I tried putting in a standard Radeon 9200, the Mac wouldn't even turn on then.

I'll keep hold of the card until I have a way to test if it is 100% dead or still going.
[doublepost=1535030569][/doublepost]

I think you mentioned that your potentially dead one was 108W, which I would look at again if I were you. I don't think that's quite right, because Apple hasn't used a PSU that weak in a Power Mac since before the G3 era. I'm thinking yours, if it's original, must have more wattage than that.

Oops! Looks like i read the wrong output for the power supply. After looking again, it says it supports a total of 360 Watts. It's an AcBel model PSU.

I personally would not go with anything less than 400W for a replacement; but that's me, I have dual processors, and don't have any idea of your particular needs. I think 300W is a reasonable minimum for a single-CPU MDD.

Specs wise, this Mac has (or had) 2GB of DDR RAM, an ATi Radeon 9000 PRO with an ADC connector, a 1.25GHz Single PPC G4, and 3 hard drives.

And for the power supply, I only have 1 that is spare, but it's an old cheap 250W "POWER MAN" PSU. I could take the 400W PSU out of my Pentium 2 PC, itself being taken out of a Dell Dimension 2400. I also have a 650W Antec PSU lying around, but I'm not sure if it has Active PFC or not.

 

[Raging Dufus]

It's an AcBel model PSU.

Apple sourced the MDD's power supplies from two vendors, AcBel and Samsung. Both tend to fail, but the AcBels are worse.

this Mac has (or had) 2GB of DDR RAM, an ATi Radeon 9000 PRO with an ADC connector

You didn't say if you're running one of Apple's ADC displays or not, but keep in mind that you'll lose the ability to power an ADC display if you switch to an ATX PSU. I'm aware of ways around that problem, but I have no experience with those.

I also have a 650W Antec PSU lying around, but I'm not sure if it has Active PFC or not.

Give it a shot. Active PFC might not cause problems for your MDD; like I said it's a different beast from the Sawtooth I had problems with. At worst, it will cause instability; but it should at least boot. It won't do any harm (at least in the short term), just might cause a random freeze-up or kernel panic.

 

[asdfguy86]

I don't have any ADC displays, so loosing proper ADC support wouldn't be much of an issue for me. I used the DVI port on the GPU, with a DVI to VGA adapter for the monitor I used with it, which is an NEC 1280x1024 display.