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Scotttheking · Mar 7, 2003, 10:50 PM

System is a sawtooth G4.

Option 1) Replace the fan in it.

How do I get the PS out to do this? Can I just put in an 80mm fan with a 2 pin tail?

Option 2) Replace the PS with a PC one.

What mods do I need to do to get it to work?

Option 3) Pay apple for a new one.

Does anyone know how much that would cost?

Any other options? Thx.

While I'm at it, what size is the case fan, and is there anything special I need, or can I just put in a new one of that size and have it work?

TimmyDee51 · Mar 8, 2003, 01:10 AM

I would go for replacing it on your own. The size is 80 mm and I would assume its a two pin. You can order a three pin fan and just swap the connectors, ditching the superfluous yellow wire.

Mac Zealot · Mar 8, 2003, 01:58 AM

yup. That's what I'd do. Might want to match your wattage/cfm flow.

Not a big deal tho. The PSU will supply X watts at X amps and that's it, it will also just work less efficently with a crap fan. You should be fine with anything

Hash · Mar 8, 2003, 05:06 AM

just change the PS altogether. i changed my BW PS unit with 200W by PC 350 W with service outlet, its silent and powerful

It can power all my USB peripherals without problemns as well as 4 hard drives, USB2 card and a combo drive

Jazzphone · Mar 8, 2003, 08:41 AM

You cange it with a PC powersupply because Sawtooth and above boards use a 22-Pin PowerSupply Connecter where as the PC uses a 20-Pin Connecter, You can just use a new fan either it use a 2/3pin connector or a molex connector it doesnt matter just get a new fan for it, no worries.

Todd Madson · Mar 8, 2003, 10:01 AM

This happened to me just last spring.

See this?

Here's the deal - you can replace the fan with any 80mm fan that has sufficient airflow.

My problem was that the fan blades had stopped and I didn't notice - it ended up trying to kill a large hard drive.

It also stressed the power supply since it's never delivered quite the same voltage since this occurred.

Replacements from Apple are God-awfully expensive.

I ended up replacing the fan with a lighted model which required a three conductor plug to light up.

That way I can see the blades spinning and know for sure it's working.

A standard high speed fan would work, but I wanted the illumination so I could see what was happening.

The Apple Power supply has a little power conductor that powers the fan inside the supply.

If that plug isn't getting a current draw, the power supply will shut itself off shortly after boot to protect itself.

I ended up using the remains of the old fan's wiring harness to connect to a resistor that came from an old GM airbag controller. Just make sure the value is sufficient to (1) let the power supply know that power is being drawn but beefy enough to (2) not burn up drawing power. I forget the value being drawn.

I then routed the fan cable outside the power supply case (it also came with a thermal sensor to detect how hot it is in the case and to speed the fan up if things are getting too hot).

When my old fan died it was doing about 120 degrees farenheit in the case.

The new fan brings things down to a cool 96 degrees farenheit with no problems so far.

The nice thing is that there is a huge variety of fans available from PC hot rodding shops (see www.tranmicro.com for an example).

If I'd been thinking I might have replaced it with a tan Thermaltake fan that has a potentiometer to speed it up. It's louder than God but I could cool the case to 90 degrees with it probably.

Todd Madson · Mar 8, 2003, 10:09 AM

Removing the power supply isn't that bad but what becomes annoying is the assembly that allows you to lock the case shut.

If you are working on the case just open the side and stick a long screwdriver in the side hole to keep it out of the way.

Good luck.

Scotttheking · Mar 8, 2003, 11:27 AM

Todd, is the connector in the PS just a 2 pin fan header?

I just grabbed a fan from my pile, it should be enough cooling, just want to know if it'll work before I take the PS apart.

I caught the fan failing within about 5 minutes, so nothing burned. It was too quiet in the room

Mac Zealot · Mar 8, 2003, 02:46 PM

lol. It'd take me longer than that to detect a silent fan. :|

Scotttheking · Mar 8, 2003, 04:30 PM

Yeah, uh, apple can go to hell.
They want something like $250 to replace it and install it, and of course, they won't let me install it.

Mac Zealot · Mar 8, 2003, 05:01 PM

WHA?!

That's insane. $250 for an ATX "P4" power supply? nah.

If I'm not mistaken, it's just a P4 style ATX server power supply. With 2 pins reversed.

And for the price of a $2 fan? Geez. Get another fan into there

I'm still rather sure as long as you use a half decent fan you'll be just fine

Hash · Mar 8, 2003, 09:07 PM

Its not just usual PC PS supply. Later Mac models have PS with additional ADC connection 24V. Fortunately, my BW didnt need it and hadnt.

Scotttheking · Mar 9, 2003, 05:21 PM

That wasn't too bad. I decided I wanted to play WC3 a lot, so I replaced the fan myself

zac4mac · Mar 11, 2003, 07:15 AM

I replaced the fan in my old duallie last year. Sounded like an MDD for a couple of days - bad bearings. The replacement was a PIA, but easier than putting RAM in my 8500.

If you can't be handsome - be handy. Red Green