QuickSilver G4 (M8360LL/A) Power Supply W/Dead Fan, Would Like To Discuss

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55 points

QuickSilver G4 (M8360LL/A) Power Supply W/Dead Fan, Would Like To Discuss

Hey Everyone,

I recently discovered my Power Mac QuickSilver G4 (M8360LL/A -- http://support.apple.com/specs/powermac/PowerMac_G4Quicksilver.html) has a dead fan within the power supply. Running an open-case test shows all other fans are working fine. Currently I have a high RPM floor fan blowing A/C air directly into/against the rear of the chassis.

I've done some research on my options, but would like some help making the best choice:

(1) Purchase a replacement power supply.

(2) Install a replacement fan directly into the power supply since it still appears to be functioning normally.

(3) Purchase a cheaper alternative, but compatible power supply?

I'll discuss my research into each possibility in order:

(1) I've found a small number of sites selling replacement power supplies for the QuickSilver G4 systems (shipping not factored into the prices I'm listing):

(a) $174.00 from DV Warehouse ( http://www.dvwarehouse.com/Power-Supply-344-W-PM-G4-Quick-Silver(733-800-867-933-1ghz/Dual)-p-20361.html)

(b) $179.99 from Mac-Resource ( http://www.mac-resource.com/store.php?item=6612513.PART)

(c) $219.95 from WeLoveMacs ( http://www.welovemacs.com/posu344wapog.html)

(d) At the time I searched, I didn't see anyone selling the same model power supply on eBay.

If I choose to purchase a replacement, I'll most likely go with the cheapest vendor since it's listing the part as new.

(2) I'm not confident enough to attempt a fan replacement, and since the power supply fan has been dead for an unknown length of time, I'm not entirely confident it hasn't been damaged from excessive heat. If anyone has a link or useful document that explains how to replace the power supply fan safely, I'd be open to the option. Right now, the most information I currently have is the physical specifications of the original fan (correct me if I'm wrong!):

Protechnic 80x80x25mm MAGIC (made by Sechang Micro)
12 Volt, 0.24 Amp
38.27 CFM, 3000 RPM (max), 29 dBA
P/N: MGA8012HS

I would probably want a better alternative if I went this route, since I didn't expect the fan to die quite this soon (although I generally run my system 24/x7).

(3) I found this other post where another G4 QuickSilver user had the same problem: http://discussions.apple.com/thread.jspa?messageID=2198292

That thread has a link to the following site with recommendation for purchasing power supplies:

http://www.Performance-PCs.com/

However, I've limited experience with voltage requirements and I don't know anything about the physical connector or dimensions of the power supply itself. At best, I know the model of my power supply is 614-0157 and can max out at 344 W.

If anyone has input and suggestions to help me fully explore my options, I'd really appreciate it. Otherwise I'll land on safe ground by buying an entire replacement of the same model, swap it out, and be done with it.

Power Mac G4 QuickSilver (M8360LL/A) Mac OS X (10.3.9) 2 GHz Processor Upgrade (Giga Designs), 1.5 GB RAM, 5 Internal HDDs

Posted on Jul 24, 2006 6:17 PM

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Answer 1

PB PM

Level 4

2,480 points

Jul 24, 2006 6:22 PM in response to AppleGeek

The power supply fan blows air out of the case, using an external fan on a closed case can hinder cooling ,as I found out when I tried this myself. The cheapest option would be to just replace the fan.

Keep in mind a PC ATX power supply would need modding to work with your G4. So unless you have some electronics experience I wouldn't advise doing it, at least without some research anyway.

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Answer 2

Jul 25, 2006 5:56 AM in response to PB PM

I agree that replacing the fan is the cheapest way to go, but it may not be the surest way. Maybe the controller in the PSU is fried, so that even if the fan is replaced, it won't turn. There's no real way to know without knowing stuff about electronics (and you can tell by the highly-technical terms I'm using that I'm no electronics guru). If you try the fan approach, it may not work and you may need to buy a replacement PSU anyhow. My .02? Go ahead and get the replacement PSU and then you won't have to muck with the fan.

Best,
~FifthWheel

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Answer 3

Jul 25, 2006 8:58 AM in response to FifthWheelAt80MPH

Caution - Working on Power Supply can be Dangerous to your Health.
There are capacitors inside power supply that hold a charge and if you accidently touch the capacitor you could be electrocuted .

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Answer 4

PB PM

Level 4

2,480 points

Jul 25, 2006 9:39 AM in response to Peter Russo

If you are worried about this, unplug the machine and press the power button after removing the battery, it will drain any power left, or you could let it sit unplugged for a few hours just to be sure.

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Answer 5

AppleGeek Author

Level 1

55 points

Jul 26, 2006 5:16 PM in response to PB PM

Thanks for the feedback PB PM! I do know the PS fan blows air out of the case, but I'm not sure about the other fans. Does Apple list information about intended airflow of each fan they install in individual systems? I ran a quick search on Apple's G4 support site for the keyword "airflow" but didn't turn up anything. The G4 QuickSilver manual doesn't mention anything about them either.

Maybe a better question would be: Can you tell me how to determine which direction a computer/case fan is intended to direct airflow without having to stick my hand on either side to see which has stronger wind?

Power Mac G4 QuickSilver (M8360LL/A) Mac OS X (10.3.9) 2 GHz Processor Upgrade (Giga Designs), 1.5 GB RAM, 5 Internal HDDs

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Answer 6

AppleGeek Author

Level 1

55 points

Jul 26, 2006 5:25 PM in response to PB PM

I decided to purchase a replacement power supply from DV Warehouse, since it was the cheapest vendor I could find selling the part as new.

When time permits, I intend to open the original power supply cover to see how challenging it would be to replace the fan. When I do, I'll add more about it to this thread.

One thing I'm noticing with this power supply fan while it's still in use with my system: If I push on a fan blade with a plastic stick while the system is powered up, I'll see the fan revolve a little (very slowly) before stopping. Not sure if that can be a useful clue as to which component within the power supply could have failed.

PB PM - About your earlier comment to blowing A/C air against the back of the case being more of a hinderance than helpful, is that true even when the component has no assisted airflow at all? In other words, my logic in using a floor fan to force colder air into the power supply is to help cool the components within it since there is otherwise only natural airflow to help keep the PS from overheating.

Thanks!

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Answer 7

PB PM

Level 4

2,480 points

Jul 27, 2006 12:39 AM in response to AppleGeek

If the PSU fan has failed, I think its likely that the bearings are shot rather than an electrical problem. I tried to clean my PSU fan a few weeks ago, yikes, too much stuff in there for me to fiddle with, since the PSU is one of the most expensive things to replace in the PM G4.

As for air flow, you need a replacement out-take (80mm) soon, without one hot air will build up quickly, since the large 120mm case fan ***** cool air in only. You can buy PCI slot out-take fans for $5-30 depending on the type you need. To be honest, keeping cool air moving through the PSU is important, so if all you are doing is moving cool air directly through the fan slot it might help, but not much since its such a small space and most of the air will get deflected back out by the now dead fan.

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