I need help raising a Dual 1GHz Quicksilver from the dead

[macaddict23]

I've never taken a mac apart before, so I'm going to need some help.

When I turn the G4 on, the fan comes on, the power button on the face doesn't light up, there's a red tiny light on the motherboard that's lit, and nothing shows up on screen. I have a few 733Mhz Quicksilvers, so I'm thinking I can pull a power supply from one and try it on the Dual 1GHz. Any clues on how I go about doing this? I've never taken a mac apart before, so the last thing I want is to get shocked. Thanks!

 

[misterredman]

I've never taken a mac apart before, so I'm going to need some help.

When I turn the G4 on, the fan comes on, the power button on the face doesn't light up, there's a red tiny light on the motherboard that's lit, and nothing shows up on screen. I have a few 733Mhz Quicksilvers, so I'm thinking I can pull a power supply from one and try it on the Dual 1GHz. Any clues on how I go about doing this? I've never taken a mac apart before, so the last thing I want is to get shocked. Thanks!

Can this maybe be of any help?

http://docs.info.apple.com/article.html?artnum=58769

 

[macaddict23]

Thank you for the link, but I have yet to decide whether it's worth replacing the power supply. Based on my description, is the culprit a bad power supply? When I press the power button, there's no chime, there's a red light on the logic board, and the fan spins.

 

[sushi]

Thank you for the link, but I have yet to decide whether it's worth replacing the power supply. Based on my description, is the culprit a bad power supply? When I press the power button, there's no chime, there's a red light on the logic board, and the fan spins.

Not sure, but it sounds like it could be the power supply.

Try reseting your PRAM. That may solve your problem.

If not, and if I understand your post, you have some other Quicksilvers. If so, double check, but I believe that power supply could be used. Since the Quicksilvers open so easily, all you would need to do is cross connect (disconnect the power supply of the affected computer, and then connect the power cables from the other Quicksilver) between the two computers. A quick way to check out if it is just the power supply. This way you don't have to take either power supply out to test.

Again, double check the power supplies are compatible before doing this.

 

[macaddict23]

Hi sushi. That might actually work. When you say disconnect the power supply, you mean to pull this cable (circled below)?

 

[sushi]

Hi sushi. That might actually work. When you say disconnect the power supply, you mean to pull this cable (circled below)?

Yes, these are the two power connectors to the Mother board.

If the power supply works, when you boot, you will see a Sad Mac face because there is no OS. But if it starts up, that is good,

If you want to completely test, before replacing the power supply, then you will need to connect power to the hard drives. This may be a little harder depending on the length of your HD power cables from the PM733. If you can't connect directly, you could get an extender cable. They are cheap.

Personally, I would go for the extender cable. As I mentioned, they are cheap. I think I got my last one for about $3. You can always use it later for something else.

Of course, shut down the computer before connecting any cables. When I do things like this I usually disconnect the power cable from the back of the computer.

 

[DoFoT9]

Yes, these are the two power connectors to the Mother board.

If the power supply works, when you boot, you will see a Sad Mac face because there is no OS. But if it starts up, that is good,

If you want to completely test, before replacing the power supply, then you will need to connect power to the hard drives. This may be a little harder depending on the length of your HD power cables from the PM733. If you can't connect directly, you could get an extender cable. They are cheap.

Personally, I would go for the extender cable. As I mentioned, they are cheap. I think I got my last one for about $3. You can always use it later for something else.

Of course, shut down the computer before connecting any cables. When I do things like this I usually disconnect the power cable from the back of the computer.

dont forget to keep connected to it with a anti-static cable!

 

[macaddict23]

Okay, please correct me if I'm wrong.
1) Disconnect the two cables shown above from the "dead" G4.
2) Disconnect the same cables from the "good" G4 and plug these cables to the motherboard of the "dead" one.
3) Connect the power cord to the "good" G4.
4) Press the power button on the "dead" G4.

Does that sound right?

 

[stevep]

I'm not sure what sort of power supplies these machines use, but it's likely they are switch mode supplies, in which case they don't like being connected to a supply when there is no load attached. In other words, make sure the hard disc is plugged in to the power supply before you connect to the mains supply.

 

[sushi]

Okay, please correct me if I'm wrong.
1) Disconnect the two cables shown above from the "dead" G4.
2) Disconnect the same cables from the "good" G4 and plug these cables to the motherboard of the "dead" one.
3) Connect the power cord to the "good" G4.
4) Press the power button on the "dead" G4.

Does that sound right?

Yes.

If you want, you can connect the HDs on the "dead" G4 to the "good" G4 to make sure that your "dead" G4 will boot up completely before you do surgery to replace the power supply.

I'm not sure what sort of power supplies these machines use, but it's likely they are switch mode supplies, in which case they don't like being connected to a supply when there is no load attached. In other words, make sure the hard disc is plugged in to the power supply before you connect to the mains supply.

There will be a load via the MotherBoard.

So it should be okay.

dont forget to keep connected to it with a anti-static cable!

Good point.

However, in lieu of a anti-static cable, the OP can be sure the two computers and himself are common grounded.

 

[spork183]

before he goes to the whole powersupply switch, shouldn't he hit and hold the cuda for a 10 count? My quicksilver pulled this and resetting put it straight (until 2 years later when the power supply went).

 

[sushi]

before he goes to the whole powersupply switch, shouldn't he hit and hold the cuda for a 10 count? My quicksilver pulled this and resetting put it straight (until 2 years later when the power supply went).

Yes, before swapping out power supplies, of course one should try other methods first.

Reseting the PRAM was mentioned above.

Probably should have mentioned resetting the Cuda Chip, in case it would matter in the OP's particular model.

The OP should definitely try this before swapping out the power supplies.

BTW, since power supplies can and do die at times, and the OP has a PM733 laying around, provided the idea of using the PM733 power supply was a quick way to test the "dead" G4.

 

[jaikob]

dont forget to keep connected to it with a anti-static cable!

or hold onto the metal part of the case while your doing it.

 

[sushi]

or hold onto the metal part of the case while your doing it.

Yep, common grounding.

 

[macaddict23]

Thanks for the responses. I've tried zapping the PRAM, resetting the PMU/CUDA, with no luck.

I'm going down to Radio Schack to pick up an extended cable with the hopes that Sushi's "cross connect" idea will work.

I've googled searched "Power Mac G4 Power Supply Replacement" but all I've came across was MDD G4 and Gigabit G4 How-Tos. Do you guys know of any resources where they show how to replace one on a Quicksilver model?

 

[berntrop]

welovemacs has a nice power supply section

welovemaxcs.com has a really nice overview of G4 power supplies, a selection wizard and oboleted an replacements.

Check that the supply from the 733 can handle the load before you accidentally fry more parts.

 

[berntrop]

I think the extender cable is a bad idea(tm)

Your time is better spent checking welovemacs, I remember some pictorials too.
<digging through old mail>
WOA

Please check the supplies if they are the same model. Pinouts have changed during the life of the QuickSilver case!!

see:
mdd supply: <http://www.welovemacs.com/posupmg4fwp6.html>

Howto to use a mdd fw800 supply in a QS 733:
<http://www.xlr8yourmac.com/tips/MDD_ps_mods/MDD_PS_Mods.html>

If you need help, post the model number of both macs.

 

[macaddict23]

The "dead" machine is a Dual 1GHz Quicksilver. The donor is a 733MHz Quicksilver. The numbers and other info are the same on both power supplies.

 

[sushi]

The "dead" machine is a Dual 1GHz Quicksilver. The donor is a 733MHz Quicksilver. The numbers and other info are the same on both power supplies.

Good to hear.

That is why I used the approach that I did. If the cross connect works, then you can transplant the power supply from the 733Mhz QS to the 1GB QS.

The suggestions above regarding the two websites are good as well. I am a bit of a tinkerer, so usually have access to cables and such so it is a quick test to see if things work.

Let us know how things work out for you.

 

[macaddict23]

Okay, I just swapped the power supplies on both the 733 and the Dual 1GHz, and it looks like the latter did not work. It was actually easier than I thought. I'm not bummed by it, because these were purchased for dirt cheap.

On a separate note, I won two college auctions for 13 Graphite G4s (450MHz-533), and 5 Quicksilvers, and one MDD. I resold all but three Quicksilvers and the MDD, (thess were added to my personal collection) and made a pretty good profit on the others.

I'm starting to collect Macs, and here are my four mint Powermacs so far. Since my collection will mainly be for display, I'm more concerned about cosmetic condition than specs.

 

[macmikey2]

backup battery?

Just a thought, but back when I was fixing these things on a regular basis, replacing the backup battery and reset PRAM would almost always bring them back. If not, a CPU swap with a similar unit did for the rest. A dead PRAM battery can muck things up preventing a successful startup.

I seriously doubt power supply has anything to do with this, I have had several that were just plain shot CPU's or motherboards.

Pull the battery and all ram and see if it boots to the error chord (no ram). Then replace the ram one stick at a time and see if it boots to normal chime. Keep HD unplugged so you don't corrupt it while turning unit on and off.

If you don't get startup chime or error chime, I would suspect motherboard or CPU. Not power supply.

Mike

 

[macaddict23]

Hey guys. I went ahead and dismantled the Dual 1GHz, hoping that I can sell the parts on eBay.

I was thinking, I'm not sure if the Dual 1GHz CPU is the problem, but is it possible if I stuck this on my working 733Mhz motherboard as a last resort?