Overclocking And Cooling Apple's MDD G4's

Currawong writes "At AppleTalk Australia, one of our members, unable to upgrade his production mirrored-drive-door G4 to a G5 due to software & hardware incompatibility, has instead has both over-clocked and made significant cooling modifications to his machine. He replaced most of the fans, including adding 4 ultra-quiet Verax fans, so the machine would run quieter, as well as cooler, in his studio. For those interested in how he over-clocked his machine, we've also posted his guide on how to do it."

speaking of overclocking Macs...

[ubiquitin]

This is almost as good as the powerbook overclocking notes [voelker.com].

Re:fan based cooling

[agent dero]

Paying $3k for the latest cool thing is so the 90's
Making do with what you have is in, get with the program

Re:fan based cooling

[rice_web]

I realize it's a joke, but if you want to talk about excess, please read something about the 80s.

Re:fan based cooling

[eboot]

Dont say that! Thats how recessions start!

Overclocking older macs

[danamania]

I must mention the always useful Clock Chipping [mac.com] page, with info on overclocking just about any archaic mac that can be. IIs, Quadras, PCI Powermacs, Performas, iMacs, G3s and G4s.

Why settle for 25MHz when you can blaze along at 33MHz?

Re:Overclocking older macs

[ColaMan]

Why settle for 25MHz when you can blaze along at 33MHz?

That's still a 33% increase though, which is a fair bit.

If you can reliably overclock a (say) 2.5GHz PIV to
3.3GHz - the same 33%, then I'd be impressed with that as well.

Re:Overclocking older macs

[g-san]

as long as I can overclock the dsp on my quadra 660av, i'm all for it. give me an excuse to pull it out of the stack of 10Mb hubs I am saving for that day when someone posts an article about overclocking them...

That's still a 1000% increase though, which is lotsa fair bits.

btw, anyone know where to get a reliable 40MB hd and OS 7.5? I need the System Enablers too. (duh, I gnow, ebay. its a joke, like the C64 loading from tape screen from GTA:VC. If you don't get it, you don't get it.)

User Ox4389 stole my

Re:Overclocking older macs

[grahamlee]

That's very very true. The difference between the NeXTstations and the TurboStations was amazing - same 25MHz to 33MHz speed bump. Of course, the difference between OpenStep on a 25MHz 68040 and on a Pentium 100 was even more impressive :-).

am I missing something?

[jbellis]

he says he overclocked a 1.42 GHz g4 to 1.5 GHz.

who the hell cares?

Re:am I missing something?

[Analog Penguin]

It looks like a dualie, so we're talking about an extra 160 MHz here rather than 80, but still...

To me, the real value in this article is not his personal account of squeezing that relatively pitiful extra performance from the thing, but the chart detailing how to nearly double the processor speed. Of course that would be ridiculously impossible to achieve, but the point is that it makes it clear enough how to be more adventurous than this guy.

Re:am I missing something?

[Phleg]

But that's eighty megahertz! It's like he clustered his G4 with the awesome power of a 486DX!

Re:am I missing something?

[Anonymous Coward]

I think you missed the point of the article.. It is not to show that he achieved an 80MHz boost but to illustrate how any MDD owner can increase their processor speed.

The first line even says that this is a step by step guide to overclocking - choose your own speed.

Also the front page of the author's site shows he had that dualie up to 1.67MHz! Check it out for yourself www.bitsandpieces.info

Re:am I missing something?

[Anonymous Coward]

oops fixed link

www.bitsandpieces.info [bitsandpieces.info]

Re:am I missing something?

[danamania]

Also the front page of the author's site shows he had that dualie up to 1.67MHz!

Commodore 64 with AltiVec!

(yeah, I know you meant 1.67GHz :)

Re:am I missing something?

[sakusha]

hey, no fair poking fun, my first computer was an 8080A running at 2MHz.

But seriously, there is no damn way I'd overclock my dualie 1GHz MDD G4. With 4 internal hard drives and the Apple swapped-out reduced noise power supply, it's already blazing hot. If I close the door to my office, and I'm doing something CPU intensive like video compression, the room temp will quickly rise to about 90 degrees, despite my central air conditioning. But then, I have a really small office.

Re:am I missing something?

[Pope]

The best thing you could do is take out the drives and go FireWire. Of course, that often just moves the noise somewhere else, but it'll help with the heat.

Re:am I missing something?

[volsung]

You are thinking of Red vs. Blue's Apple Switch parody [redvsblue.com].

What's the point?

[CompVisGuy]

So, *why* was this a good thing to do? The only reason to overclock would be to improve performance, but the article doesn't give any before and after performance measurements.

Given that so many factors contribute to computer performance (CPU architecture, number of caches, size of caches, bus speed, memory size, disk performance, CPU frequency), often in nontrivial ways, increasing the clock speed by such a small amount is unlikely to offer any significant increase in performance.

not a big improvement

[Anonymous Coward]

I doubt it would help much.. The biggest bottleneck in G4 systems is the bus speed, not the processor speed. Sure the processor is a bit faster, but what does that matter if the bus couldn't feed it fast enough in the first place? I'm sure it will help in some situations, but the biggest thing the G5 has over the G4 is that big fat bus.

Reduced noise is more important in this case

[ZiggyM]

I own a dual MDD too. The machine is extremely (50 dBA+ @ 1 meter) loud, its driving me crazy. The fact that he made it quieter would be enough for me to attempt a mod (he has not posted actual dBA values for comparison, though.) I have just been researching such a reduced noise mod, and, for anyone interested, the best one Ive found (there are many in there) is at G4Noise.com (yes there is actually a website dedicated to this issue.) In there, someone managed to reduce the 50 dBA to 30 dBA [g4noise.com], making simple modifications. The guy gave a lot of thought to the heat dissipation issue and found very clever ways to improve apple's design, such as a simple cardboard mod that makes a huge difference to cool air intake.

The next thing to do....

[jhesse]

Is add lighting [unl.edu]