Become a MacRumors Supporter for $50/year with no ads, ability to filter front page stories, and private forums.

Reflex88

macrumors newbie
Original poster
Feb 5, 2004
12
5
Aye-Up..

So I dusted off my 2 Mac Minis to see if they could cut it with a little over clocking.. How? Well, you've all seen you can move the resistors around.. I tried and failed to re attach them once removed but found a work around.... A PENCIL! Yup.. the graphite is enough to short the pads and confiure the multiplier, plus, you can rub the thing clean with a normal rubber (this is an american site? eraser, then) and re do them until you find a stable config! Brilliant!

Any Who.. The 1.25ghz is VERY happy at 1.5ghz and the 1.42ghz gets by at 1.75ghz but is much happier at 1.67ghz...

I'm going with the 1.25@1.5 because it's only the teeniest smidge slower then the 1.42@1.75 and just feels more stable with much less fan...

I've clocked the ATI card up by 20%... it was 25% but long video playback seemed to upset it.
http://thomas.perrier.name/ - I used this great preference panel that does live overclocking.

Now, the modern internet.. tried tenfourfox, left me a bit cold.. So I updated the webkit in safari and that works well enough for me.. I found the updated webkit here - https://sourceforge.net/projects/leopard-webkit/

HOWEVER! Flash/html5 was a ball ac.. you tube would play ok once fully buffered, which, once you've updated safari, doesn't happen any more...

So, I stumbled across this thread for "the fastest flash"
https://forums.macrumors.com/thread...layer-plugin-for-ppc-macs-on-the-web.1462608/

I installed it and, sure enough, you tube (at 360) plays back smooth even in full screen, but not only that.. it buffers in full now if you leave it too!

My question is.. does anyone actually know what this plug in does? The original youtube video has long gone and I'm just intrigued.. it reports as flash 10 but the control panel is from version 8?!?

EDIT
After some tinkering, I thought I'd messed up my flash, but it turns out that because the tweaked flash has elements of flash 8 in it, YouTube etc doesn't find it compatible when it comes to playing back ads, as a result, it'll stop working if you don't use it in conjunction with an ad blocker....
 
Last edited:
Though you probably wouldn't want this, you'd actually get 3rd degree burns, could one theoretically do the same process to a PowerBook G4? Mine's a 1.25ghz. Cool find tho! I really want to get a Mac Mini now haha

Honestly when I first saw this thread I thought of Rabidz7
 
That Leopard Webkit is from December, and in fact it really was only some patches, or whatever. It has not been updated in over half a year now as Tobias says it is stable. But what about security?

As was said by Cameron:

"I'm not sure what that was, but the core dates from October, unless he's uploading them somewhere else?"

Tobias replied a few days later:

"I don't feel motivated to backport WebKit 601 (Safari 9) or later to C++03 (gcc 4.2) mainly for the following reasons:
- WebKit 600 is very stable
- vast majority of web sites do still fully support WebKit 600
- backporting might easily take some months (and it cannot be ported incrementally but needs to be almost completely done before the first test run)

My original motivation for beginning with Leopard WebKit was unstable and outdated WebKit on OS X 10.5 - and that goal seems to have been accomplished now.
But who knows - might be I'll finally try to get the JavaScriptCore JIT working."

http://tenfourfox.blogspot.com/2016/01/3860-available.html#comment-form
[doublepost=1463973796][/doublepost]And here is the most recent hacked Flash:

https://forums.macrumors.com/threads/flash-v21-0-0-216.1967041/
 
I installed it and, sure enough, you tube (at 360) plays back smooth even in full screen, but not only that.. it buffers in full now if you leave it too!
On my 1.67 Powerbook 17", this plugin raises Youtube playback from 80% to 100% CPU with no improvement to playback ie a little stuttering before it's buffered. Maybe works better on certain setups?
 
I pushed my 1.5 ppc mini to 1.83ghz. Wasn't stable at all, apps wouldn't load, etc.
Dropped down to 1.75 and it runs real well ;) What was the base clock speed?
 
I pushed my 1.5 ppc mini to 1.83ghz. Wasn't stable at all, apps wouldn't load, etc.
Dropped down to 1.75 and it runs real well ;) What was the base clock speed?
I wonder if it is a cooling issue, make sure it is pasted right, and the fan has plenty of movement.
 
while not directly related to over clocking. I had a Radeon 9600 G5 card where R121 in the pic, a (I think) 3KΩ SMD resistor had fallen off and due to being part of the voltage regulation caused the card to artefact. i was quite annoyed about this as it was decent Core image Card that can also be easily fitted to G4s. so it sat around for a while then i stumbled across this thread and decided Screw it lets try Bridging the gap using a soft graphite stick and rub it in good and well it worked! card works lovely (currently in my PowerMac G5 Linux box replacing a R9200 i had in it) (FYI I do have a 1.42Ghz Mac mini thats currently looking at me in fear :) )

upload_2016-5-23_21-6-24.png
thats my repair Job heh

upload_2016-5-23_21-8-1.png
and here you can see it running :)
 
That's brilliant! the mighty pencil not only overclocks, but it FIXES too! Ha!

My two Mini's were a 1.25 (now at 1.5) and a 1.42 that runs stable, but very heavy on the fan at 1.75. The 1.42 did actually boot and run at 1.83, but fell over a bit to often...

It's worth mentioning I slapped on some replacement heat transfer compound.. I think it's the key to the 1.25@1.5 being so happy.. that, and it was an early 1.25 so had the same heat sink as the 1.42 came with.. I've read that the later 1.2s had a smaller heat sink.

I've got the resistor bridge chart for the various speeds from a site that I kept losing and isn't in english, but they seem correct, if anyone wants me to post them up here?

Back to the internet... a 6 month old browser doesn't scare me.. as long as it's stable and I don't do anything stupid I think I'll be ok.

So do we think this flash plugin I linked removes some kind of processor cap, then? Does anyone know for sure? Or did anyone ever watch the missing video about it? It definitely improves my video playback and just getting youtube to fully buffer under flash is brilliant as TenfourFox was just sluggish on my system.
 
Last edited:
thanks :) it would be Nice if you could post your jumper chart as i have only found one that goes past 1.58Ghz, and its really low res so its hard to make it out (I can if i look very closely but if you have a better one on hand that be nice :) ) also this is my 500th post woo (if this was the old forum software i would be able to get an avatar now heh)
 
Just wanna say I had a crack at over clocking my Mac mini G4 using this way. got it stable at 1.67Ghz (1.75 boots but is unstable) overall I am quite chuffed it works (ideally conductive ink would work best if you cant solder the pads but i dont have any of that) I really need to get a 1GB RAM stick for it :)

heh__.jpg
 
I've clocked the ATI card up by 20%... it was 25% but long video playback seemed to upset it.
Hi, uhm... unless you're running some obscure mpeg2 quicktime decoder hardware and software on a desktop ppc mac, I don't see why on earth your gfx card would even care? Did you possibly hack snow leopard's VDADecoder into running on powerpc?

Also, the fastest flash browser for me is webkit 537 something and ending with the digits "69".
 
Last edited:
No no no.. You've got it all wrong.... you simply draw a mac pro and attach a thunder bolt socket and AA battery and boom! Fastest mac graphite can draw ;P

I'm sensing some peeps think this is all a bit pointless, and it probably is, but I loves me some tinkering.

As for the graphics over clock... I don't pretend to know what I'm doing with that... Why would a 20% increase in graphics chip speed and memory chip speed not give an increase in graphics performance? surely any thing osx is using these components for is now being done in less time?
[doublepost=1464163686][/doublepost]Something that pleases me going back to PPC is that I can use my digidesign Mbox as my system audio interface again! Brilliant pre amps, itunes in much higher quality basically...
 
Have just switched from the 1.25@1.5 logic board to the 1.42@1.67.. It seems a smidge quick (as you'd expect, a teeny amount).. but, I dunno.. The 1.42 used to always feel a bit "distracted" even before it was over clocked... a new HDD has helped (amazon uk were dumping thier hypertec stock, so "dell laptop" specific drives were super cheap compared to naked drives, just need to work out if it's ide before buying)

Any know why this 1.4@1.67 might have always seemed unhappy? Are some systems just grumpy and other happy? The 1.25 has always been sluggish but kinda happy... it's really difficult to describe.
 
As for the graphics over clock... I don't pretend to know what I'm doing with that... Why would a 20% increase in graphics chip speed and memory chip speed not give an increase in graphics performance? surely any thing osx is using these components for is now being done in less time?
Because all the processing taking place during full screen video playback is done through the CPU and altivec. GPU doesn't do anything.
 
Because all the processing taking place during full screen video playback is done through the CPU and altivec. GPU doesn't do anything.

That makes sense...

So what kinda stuff IS the graphics chip used for? Animating "hidden dock" and the like, perhaps?
[doublepost=1464692056][/doublepost]Here are the higher speed settings.. This graph is a bit backward, 0 means resistor and 1 means no bridge.. also, note, the order of the columns doesn't match the order of the resistors.

Also, incase you haven't read it else where, R52 is next to the processor, under the heat sink.. it DOES have to come off to remove R52.. but if you're clocking up that high, you should at least renew the transfer paste anyway..
 

Attachments

  • ameliorer_macmini_11.jpg
    ameliorer_macmini_11.jpg
    17.4 KB · Views: 408
Last edited:
I have several mini's that have run fine for years at 1.75GHz. A few of them would run for a while at 1.82, but they'd have issues eventually. I never messed with the voltage, just the pll jumpers.
 
Sorry for bumping this back from the dead, but I'm onto this, and it seemed to make more sense to bring back this thread than to make a new one.

I have a bunch of stock 1.5 GHz Mac mini G4s, and I'm willing to try to get one of them to reach 1.82 GHz, the maximum clock found in Reflex88's table, the thread starter. But I also want to make it stable. Viable, perhaps. There may be a fault in the following reasoning, but I figure the most likely reason 1.82 GHz is less stable is because of heat.

As such, I'd love suggestions & overall pro-tips on how we could bring CPU temperature down on this Mac mini model as much as possible. Reapplying the thermal paste & making sure to use high quality silver thermal paste (i.e. Arctic Silver, but not one of the fakes such as Arcticline Silver etc.) is the bare minimum that ought to be done in our overclocking scenario, but I'd also love ideas to take it a bit further, if anyone has them!

All I could think of is only the most simple:
- Change heatsink (is there one that is bigger and/or of a more heat-transfering material than the one that comes stock? Reflex88 mentioned he also had heard that later 1.2 GHz minis came with a worse heatsink than earlier ones...);
- Change fan (bigger and/or stronger fans could be used? What voltage ought they not surpass?).

I guess more hardcore & non-ideal solutions would be to keep the upper lid removed for maximum air ventilation, and also install a liquid-cooling system (lol), but such extreme measures would take away all the point of the Mac mini G4, in my opinion! Not that I think anyone wanting to do so should be stopped, though. In fact, it'd be kind of cool to see...
As for changing fan & heatsink, does anyone know what are the biggest dimensions we can consider?

Ultimately, my mission is too see how much we can push such a compact, convenient Mac OS 9 box like the mini! (Also a convenient OS X, GNU/Linux, BSD & MorphOS box!)

But if we just can't address the thermal issue for 1.82 GHz, then of course the fallback plan would be to settle with 1.75 GHz. :(
 
Sorry for bumping this back from the dead, but I'm onto this, and it seemed to make more sense to bring back this thread than to make a new one.

I have a bunch of stock 1.5 GHz Mac mini G4s, and I'm willing to try to get one of them to reach 1.82 GHz, the maximum clock found in Reflex88's table, the thread starter. But I also want to make it stable. Viable, perhaps. There may be a fault in the following reasoning, but I figure the most likely reason 1.82 GHz is less stable is because of heat.

As such, I'd love suggestions & overall pro-tips on how we could bring CPU temperature down on this Mac mini model as much as possible. Reapplying the thermal paste & making sure to use high quality silver thermal paste (i.e. Arctic Silver, but not one of the fakes such as Arcticline Silver etc.) is the bare minimum that ought to be done in our overclocking scenario, but I'd also love ideas to take it a bit further, if anyone has them!

All I could think of is only the most simple:
- Change heatsink (is there one that is bigger and/or of a more heat-transfering material than the one that comes stock? Reflex88 mentioned he also had heard that later 1.2 GHz minis came with a worse heatsink than earlier ones...);
- Change fan (bigger and/or stronger fans could be used? What voltage ought they not surpass?).

I guess more hardcore & non-ideal solutions would be to keep the upper lid removed for maximum air ventilation, and also install a liquid-cooling system (lol), but such extreme measures would take away all the point of the Mac mini G4, in my opinion! Not that I think anyone wanting to do so should be stopped, though. In fact, it'd be kind of cool to see...
As for changing fan & heatsink, does anyone know what are the biggest dimensions we can consider?

Ultimately, my mission is too see how much we can push such a compact, convenient Mac OS 9 box like the mini! (Also a convenient OS X, GNU/Linux, BSD & MorphOS box!)

But if we just can't address the thermal issue for 1.82 GHz, then of course the fallback plan would be to settle with 1.75 GHz. :(
Code:
dev /cpus/@0
: set-dfs-low               
  pvr@ 10 rshift 8003 <> if
    exit
    else
    hid1@ 1 1f 9 - lshift or hid1! 1 ms 4 1 gpio!
    then
  ;
set-dfs-low
bye
 
Register on MacRumors! This sidebar will go away, and you'll see fewer ads.