I have an old PowerMac G4 from the Sawtooth generation. I’ve had this box since 1999 and it’s still going strong. Sure it’s not the latest bling bling hardware, but I don’t care. It still works.

So a little background on how I got here.

Lately I’ve been playing around with H.264 for video encoding. It takes time for my dual G4 to chew through a file (a 20 minute video, deinterlaced, takes about 3-4 hours to encode) but man dose it do a good job! The quality is indistinguishable from the source, but the file size is way smaller. With an average bit-rate of 1000, that 20 minute video takes up 190 MB. I’ve even encoded with an average bit-rate of 700 and had acceptable quality with a 140 MB file.

So raise your hand if you knew iTunes could handle video. Yep, there’s a video iPod out there. I don’t have one, and honestly I don’t really want video on my iPod. However I do have S-Video out on my old PowerMac, and iTunes combined with Front Row makes a compelling combination. Granted Front Row only works on the new Macs…right? I’m disappointed in you young Mac Jedi. When the Dark Side told you that Macs can’t be tweaked, they lied. It’s very possible.

Now for those of you who want PVR capability, this dosen’t have it and that’s intentional on my part. Honestly I don’t care anymore. Commercial TV has sucked so bad lately I wind up watching my DVD’s more than anything. So can you do PVR on your Mac? Sure. Am I going to do PVR on my Mac? Nope.

I hooked my old G4 to the TV and it worked like like a charm. One big problem though; while watching a movie I really noticed how loud the old G4 is. We’re talking fan noise here. Lots of it. So my first goal is to make my old Mac quieter. Along the way I’ll be changing some components and building a custom case to hopefully optimize cooling so I don’t have to move air through it like a tornado.

1. Step One: New Power Supply.

The biggest auditory offender is the power supply. It’s got two little fans in there that pretty much run flat out all the time. And they have to. Using a cheap little thermometer I measured the inside of that case at over 140 degrees farenheit!

Obvioiusly we need to cool the whole case better if we’re going to rely less on the PSU for cooling duty. Thus my intention to build a case. Sure I could buy a PC case, but then I would have…wait for it…a PC case. That’s not “Thinking Different” in my book.

Patience young jedi, we’ll get to the case. But first we need to address the power supply.

If you want a genuine Apple power supply for the Sawtooth PowerMac, you can get one. The down side is they’re expensive and they still have those loud little 40mm fans. Now on the PC side of the fence there are lots of quiet PSU options. Wouldn’t one of those work? Well thanks to an article on Xlr8yourmac, we know that an ATX power supply can be modified fairly easily to work with my Mac.

DISCLAIMER: If you haven’t figured it out by now, what I’m going to do requires willingness to screw up and blow up your computer. If you are a sissy who can’t accept the consequences of your actions, do yourself a favor and stop now. Don’t blame me if you mess things up, I’m doing this with the full realization that I may permanently kill my old G4.

So I picked up a nice little Antec PSU, not the quietest in the world, but hella quieter than my current PSU. Now I could have just modified the motherboard power cable directly, but since I know myself pretty well I picked up a 6 inch cable extender. The idea here is you make your modifications to a $6 part instead of a $90 part. This also gives us the benefit of changing to a completely different PSU sometime in the future without the necessity for cable surgury again.

I deftly managed to solder the wires together, and even got the right ones on the first try! Taped the exposed metal up and hooked the Antec PSU into the PowerMac motherboard with my modified extender cable.

(a moment of silence please)

Remember to check and see if you PSU needs to be switched. Failing to do this may lead to fried computer. In my case it was already set to 115.

I took a deep breath, plugged in the AC and turned on the Mac. No pops. No bangs. No puffs of magic smoke. The cpu fan kicked on, the Antec PSU fan spun up and seconds later I had my login screen. And I must say it’s much quieter. I can actually hear the fans on the CPU heat sink and the Radeon 8500 now. I’ll deal with those as the case design comes together.

So step one down this road was a success. Step two is where things will really start to get fun as I disassemble the old G4 and start to plan my case design. It’ll have to appeal to my asthetics as well as meet the cooling requirements, however for now I’ve successfully taken a first step into the modding world.

(Baby steps man, I know changing power supplies isn’t really all that complicated, but one thing at a time.)

The Quest to Silence a Mac
Mon June 19 2006

Building The Basic Box
Sat September 02 2006