Mac OS 9 Lives

Classic Mac OS Hardware => CPU Upgrades => Topic started by: domii on February 27, 2022, 03:55:23 PM

Title: Mac Mini G4 Overclock just because its fun.
Post by: domii on February 27, 2022, 03:55:23 PM
I know this has been covered before in an old thread, but thought I would start a new one as parts where incomplete.
And it is always a struggle to find the multiplier settings when you need them when many of the old sites have disappeared.

So will post what I have and edit this in future if I make any better progress. Feel free to add anything that would help.
And it is fun - 1.8GHz puts out benchmark numbers over 1000 for geekbench, thats MDD territory.
MacOS 9.22 is ridiculously quick.  Will be posting some Unreal Tournament and Quake fps numbers shortly.

On the backside the resistors R355, R351, R358, R362, Essentially removing them all gives you 1.5GHz
Which should be possible on all the models.

R52 - next to cpu under the heatsink. R52 is important as it provides values above 1.58GHz

You can even use a lead pencil or one of those conductive pens to bridge the pins - providing speeds from 1.67 up to 2GHz.
(there is a 1.92GHz setting with evengthing bridged, not sure if anyone has tried that one, but I would like too in near future)

Some things I found on other threads.
1.25 -> (1.42 safe) or 1.5GHz
1.42 -> (1.5GHz safe) or 1.58/1.67GHz, there is even a chap on youtube with a video claiming 2.0GHz with a massive heatsink.

Late model versions
1.3 -> (1.58GHz safe) or 1.67/1.75GHz
1.5 -> (1.67/1.75 safe) or 1.8GHz

* Obviously replace the heatsink pad/paste with something decent when you do the mods to help with the thermals.
* Also a good time to replace the battery and give it a could cleaning/blasting with air.
* And upgrade the hard drive if you havent already to a mSata SSD using one of those adapters.

The main drawback is heat & voltage. I haven't figured out how to adjust the voltage.
It seems the cpu will go to 1.8GHz with the stock blower and Aluminum heatsink. Which is not horrible, they are well designed for the tiny space.

But I would like to go copper as it would most likely provide up to 50% better heat dissipation on something this small.
After which I might give the 1.92 & 2GHz speeds a go.  (which is silly speeds)

Took some measurements and pictures.

Stock aluminum finned heatsink. 40mmx50mmx20mm.
The Cpu pushpin mounts, 35mm spacing between posts. (or 49mm on the diagonal).
60x60x15mm, 12v 2pin blower flan.

I could probably cut/hacksaw a heatsink smaller and drill the holes if needbe, just need to find something suitable out there.
Might replace the blower as well if there is something more silent. Noctua has good stuff but not sure if they have a 60mm blower. There does seem to be various generics on Amazon - not sure if any are better than stock though.

* I know dosdude1 is doing a full on 7447B chip replacement that rocks 2GHz nicely.
* There was a chap that wired dip switches to the resistors and figured out many of the settings on a thread somewhere. Booted his 1.33 mini all the way to 1.92GHz.
Title: Re: Mac Mini G4 Overclock
Post by: FBz on February 27, 2022, 04:07:31 PM
Impressive!

Especially for all you speed demons out there. ;)
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: teroyk on March 01, 2022, 02:23:04 AM
I just think: How about underclocking to 1.00 Ghz with big copper heatsink...fanless solution possible?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: smilesdavis on August 26, 2022, 10:04:37 PM
i think even if we need to stick out a heatsink like an old drag car a fanless solution is the only way to go
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: teroyk on September 16, 2022, 06:37:44 AM
i think even if we need to stick out a heatsink like an old drag car a fanless solution is the only way to go

That was what I thinked too :)
Is there anybody who can test is underclocked fanless solution possible?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on October 15, 2022, 06:44:59 AM
Hello, I am writing to you from Spain. I have a Mac Mini G4 at 1.42 that I want to use for OS 9.2.2 (Now I write to you from the Classilla browser inside Mac OS 9). I'm searching the internet and I can't find overclock resistor settings for speeds above 1.58GHz. My intention is to reach 1.67GHz, but all the photos on the internet are disappearing. Can someone post a photo of the resistor positions, for speeds greater than 1.58GHz? Thank you.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: sonicsky on October 26, 2023, 08:57:58 PM
hello I'm come from china shenzhen, I find the Power10.2 Model is different from the Power10.1 Model
Power10.2 Model jumper set  R351 R355 R358, is different from this article
https://thehouseofmoth.com/ppc-overclocking-station/#G4mini

Does anyone known all the new jumper set in the  Power10.2 Model?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: FBz on October 26, 2023, 10:50:08 PM

If you have the 1.33 GHz model - House of Moth mentions a fifth resistor that he had yet to locate.

To set the jumpers for 1.33GHz, a 5th resistor has to be located (as it needs to be removed).
With the 5th resistor, for now, permanently enabled, you can only configure for the 4 clock speeds shown above. A common belief is that the 5th resistor is always enabled and acts as a ground but that does not work as the 1.33GHz configuration needs that resistor removed. Comparing a 1.33GHz board with another G4 mini board should help in locating that 5th resistor. Once this is located I will update this page.”
  - House of Moth

You may however wish to review this thread…
http://macos9lives.com/smforum/index.php?topic=4408.0
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: sonicsky on October 26, 2023, 11:58:15 PM
So is there any possible to replace the CPU to he hign model 7447A, for example 1.5GHZ and 1.667GHZ and overclock again?
 I bought the two model from ebay
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: FBz on October 29, 2023, 08:41:33 PM
@sonicsky Have you removed the heatsink from your PowerMac 10,2? (Actually a 1.33 GHz Mac mini?)

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12896;image)
                                                                                                                                               sonicsky's images
If you have the heatsink off, do you see a resistor @ R52?

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12898;image)

Better view:

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12902;image)
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: sonicsky on October 29, 2023, 08:56:45 PM
@FBz, I have not tested the 1.33 GHz Mac mini,
now I decide to change the 1.25GCPU to 1.5GHZ MC7447B HX1500YH QND0645, and set the jmuper to 1.58GHZ first
If the result is ok, and I will change the 1.33 GHz CPU to 1.67GHz MC7447B HX1667ZF QUD0529 and the jmuper to 1.83GHZ last.

I worry the overclock due to cpu power is not enough,  so did i change the adpater to 110W make it normal use?
My aim is to overclock the Mac Mini G4 and Long-term use, thx you give me the graph to compare the jmuper set,
I will take off the heatsink and check the 1.33GHz whether the R52 is different
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: FBz on October 29, 2023, 09:13:47 PM
Over 1.5 GHz you probably should increase the CPU voltage ...

You may need to make other changes to the board to increase the power to the CPU - for anything above 1.5 GHz.
What, I do not know.

But maybe 1.67 is possible without changing the CPU to 1.67GHz MC7447B HX1667ZF QUD0529?
OR 1.5GHZ MC7447B HX1500YH QND0645?

You have a 1.25 GHz mini? I thought your pics were of a 1.42 and a 1.33 GHz? ???

Maybe the 1.33 GHz PowerMac 10,2 already has the R52 removed? You will tell us.

The 1.42 GHz PowerMac 10,1 may have the R52 (which may need to be removed?).
                                                        [1.25 GHz Mac minis DO have the R52 in place.]

   (http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12904;image)

I'd suggest that everyone re-read domil's first post in this thread (at the top) above.
http://macos9lives.com/smforum/index.php/topic,6226.msg46606.html#msg46606

AND Roman78's comments over on this other thread too...
http://macos9lives.com/smforum/index.php/topic,4408.msg31058.html#msg31058
Title: 1.33 GHz Mac Mini?
Post by: FBz on November 03, 2023, 09:27:19 PM
A question for those that may have one of these specific, stock G4 Mac minis.
(Still awaiting a response on this from @sonicsky. So, anyone else with a 1.33?)

     1.33 GHz Mac Mini ONLY

Q: Is there a resistor present at the R52 location (under the heatsink)?

    (http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12902;image)
       Resistor location red-dotted here on a 1.25 GHz Mac mini.


And if you’ve ever removed (or tried to remove) your G4 Mac mini’s heatsink, you might try this:

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12950;image)
                                                          Easier heatsink removal, with a nylon spacer and steel pin from the backside.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: sonicsky on November 05, 2023, 07:12:42 PM
@FBz Yes you are right,  The PowerMac10.2 1.33G Model do not  have the jmpuer,
And I test the change the PowerMac10.1 1.25G CPU to 1.5GHZ MC7447B HX1500YH QND0645,
then overclock it to 1.5GHz, it can not work, I don't konw why? Maybe the CPU is different?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: FBz on November 06, 2023, 07:05:37 AM
@sonicsky / The new CPU does not work? Could you change it back?

Still not certain that your mini was a 1.25 GHz to begin with - as the “backside” resistors matched both 1.42 GHz minis here. (R351 & R358 present.) *Unless someone had already changed your 1.25’s resistors around before.

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12956;image)
 A 1.25 here (left side) - and your two are the middle and right examples.

And have not tested this yet, but removal of all four backside resistors from a 1.25 and the 1.42 GHz Mac minis - should yield an overclock of 1.5 GHz. (OR optionally… leaving only R358 in place should net an overclock of 1.58 GHz.) Both instances with the original CPUs and R52 in place.

Thank you for confirming that the 1.33 GHz mini does not have the R52 present.
Overclocking the 1.33 GHz mini will be different than the 1.25 & 1.42 and should not require a CPU swap.



AND if you check the link in the next post below here, you'll note that they found
a similar CPU [to the one that you placed in your 1.25(?)] already in their 1.5 GHz mini.

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12960;image)
Title: 1.5 GHz to 1.83 Mini Overclock
Post by: FBz on November 06, 2023, 08:23:29 AM
Thinking about overclocking a 1.5 GHz Mac mini?

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=12958;image)

Found this obscure gem from one of our Czech “Mac comrades” concerning overclock of 1.5 Ghz Mac mini
to 1.83 GHz. A very intensive resource.

Translated via Google Translate… to English:
https://www-amigaportal-cz.translate.goog/node/156189?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp
(Hope this works for everyone.)

If not... the original (Czech) version: https://www.amigaportal.cz/node/156189
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: DieHard on November 06, 2023, 08:50:25 AM
From the article referenced by FBz:

This is what my processor looks like - it's an MPC 7447B, and according to the factory code, it's rated at 1500 MHz.
This is good news because the "B" type was capable of higher frequencies than the "A" type.
Searching the web shows that "B" types are capable of going up to 2 GHz in practice.


Damn, 2 Ghz with a 9200, that's an amazing OS9 rig for it's size :)

Hey FBz,

Is the "A" or "B" just random luck ?  Or is there a pattern for which minis have a "B" series CPU ?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: FBz on November 06, 2023, 09:19:51 AM
Hey FBz,

Is the "A" or "B" just random luck ?  Or is there a pattern for which minis have a "B" series CPU ?

Dunno... without pulling the 1.42 and 1.5's here apart again. I'll check eventually. More homework!

BUT the lowly 1.25 mini that is now open here does have an MC7447B. (I just can't quite make out its' MHz rating - but it isn't 1500 MHz / if that does make a difference.) And I have found no references to successful overclocks noted of 2 GHz. Cooling being the big concern. And if my memory serves me well, I think there was a mention of attaining 1.92 with some stability.

Ahh, Roman78 took a 1.42 to 1.92 http://macos9lives.com/smforum/index.php/topic,4408.msg31132.html#msg31132 but it crashed running XBench. Additional info (also from Roman78, I think) was later posted to Applefritters. Sorry don't have that link handy. ::)
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: Philgood on December 11, 2023, 11:17:56 AM
Just read this over at macrumors. Could be interesting.

https://forums.macrumors.com/threads/g4-7448-and-7457-swap.2233532/page-11?post=32783020#post-32783020
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: DieHard on December 11, 2023, 12:30:13 PM
Just read this over at macrumors. Could be interesting.

https://forums.macrumors.com/threads/g4-7448-and-7457-swap.2233532/page-11?post=32783020#post-32783020

Wow, he has stable results for a Mini running 1.92Ghz, we really gotta get this duplicated and documented here if possible
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: aBc on December 11, 2023, 12:48:04 PM
Especially interesting considering sailorMH’s success with a 1.5 GHz mini… overclocking it to 1.83 (stable). AND the notion that greater overclocks might be possible with more knowledge of voltage / current adjustments (as indibil has now provided). Maybe it won’t be necessary to replace the MC7447B on the 1.5 GHz model minis… WITH adequate voltage / current adjustments?

(However, might still need to change the 1.25 GHz models?)

sailorMH’s translated link again:
https://www-amigaportal-cz.translate.goog/node/156189?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp

Still no 1.33 GHz Mac mini example available here.

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=13056;image)

Thanks for the heads up, Philgood! ;)
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: IIO on December 11, 2023, 04:13:42 PM
how´s the 1.5 a B and the 1.4 an A when the 1.5 is a "silent upgrade" to the 1.4?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: DieHard on December 11, 2023, 04:55:59 PM
how´s the 1.5 a B and the 1.4 an A when the 1.5 is a "silent upgrade" to the 1.4?

Because apple's definition of "silent upgrade" means...
1) WE are Gods and... we are going to change as much as possible... including the CPU and vRAM
2) WE are Gods and... we are going to document as little as possible... possibly nothing
2) WE are Gods and... may leave the price the same, hike up price for no reason at all (like they did to EU on Mac Pro), or shave off a couple bucks (the rarest choice)
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on December 12, 2023, 12:11:07 AM
Hello, here I have explained how I managed to increase the voltage and current limit to a Mini. In my case I have done a SWAP with a 1.67GHz MPC7447B and I have reached 1.92GHz, but it can be used to achieve a greater overclock with a stock processor.

https://forums.macrumors.com/threads/g4-7448-and-7457-swap.2233532/post-32783020 (https://forums.macrumors.com/threads/g4-7448-and-7457-swap.2233532/post-32783020)

Here my blog:

https://rosysumenteinquieta.blogspot.com/2023/12/mac-mini-g4-192ghz.html (https://rosysumenteinquieta.blogspot.com/2023/12/mac-mini-g4-192ghz.html)
Title: Re: Mac Mini G4 Overclock
Post by: aBc on December 12, 2023, 05:05:26 AM
"WE are Gods and…"

Reminds me of that movie title - and a great movie too: “The Gods Must Be Crazy”.

And here’s another little example of weirdness.
Stated earlier that there was no example of the 1.33 GHz Mini here.
Well, not my location… but @sonicsky did post an image of his processor.

(http://macos9lives.com/smforum/index.php?action=dlattach;topic=6226.0;attach=13080;image)

And if you can make it out from the image, that’s also a “B”.
So are they all “B” except for the 1.42 GHz models?

@snial and @max1zzz (over on 68Kmla) report having 1.33’s.
*1.33’s are only G4 Mac minis with the R52’s absent / stock.

Just when I was almost, finally, going to button-up all minis here.
Have asked @indibil if the MAX1993’s are all set same / each version.

And when he says MAX1993 is “tiny” - he means tiny!

Google translate of @indibil’s blog:
https://rosysumenteinquieta-blogspot-com.translate.goog/2023/12/mac-mini-g4-192ghz.html?_x_tr_sl=auto&_x_tr_tl=en&_x_tr_hl=en-US&_x_tr_pto=wapp

I don’t relish the idea of changing processors, but I might “adjust” the MAX1993. ;)

AND are the 1.33 and the 1.5 GHz - not Motorola (but "silently" Freescale processors)?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on December 12, 2023, 05:15:51 AM
I only have this original Mini at 1.25 and another original at 1.47. I have only measured the values at 1.25.

I have identified the resistors in the photo, I would have to take the tester and measure (with a magnifying glass, hehe)

Adding 330k or 220k in parallel changes the value little, it is not risky.
Title: Re: Mac Mini G4 Overclock
Post by: aBc on December 12, 2023, 05:54:15 AM
@sailorMH achieved stable 1.83 GHz with a stock 1.5 GHz processor by changing resistors
(and R52). NOW with the updated, “indibil MAX1993 approach” for voltage / current
increases, perhaps greater than 1.83 GHz (stable) is possible and with a stock 1.5 GHz
processor? Too bad that @sailorMH is off for the holidays and likely not to return until
after the New Year… or we would know more about this much sooner.

Me? I can’t decide if I want to try this on a 1.25 or a 1.5 GHz.
(And I now have a headache!) ::)

@indibil:
And… how about a “final” picture with 330k or 220k in place as it is working now?
*For you to achieve 2.0 GHz - will you need to remove R52 and only have R362 in place? ;)

GREAT WORK! indibil.
Title: Re: Mac Mini G4 Overclock
Post by: ssp3 on December 12, 2023, 06:13:47 AM
AND are the 1.33 and the 1.5 GHz - not Motorola (but "silently" Freescale processors)?

FYI, Freescale is (was) Motorola.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: robespierre on December 12, 2023, 10:51:29 AM
The semiconductor division of Motorola. The radio/defense/contractor divisions are still Motorola.
Freescale merged with NXP (formerly the semiconductor arm of Philips N.V.) in 2015.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on December 29, 2023, 09:48:24 AM
Hello, i have added a copper heatsink in my Mac Mini 1.92GHz

I attach some pics.

https://rosysumenteinquieta.blogspot.com/2023/12/mac-mini-g4-192ghz-con-disipador-de.html (https://rosysumenteinquieta.blogspot.com/2023/12/mac-mini-g4-192ghz-con-disipador-de.html)
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: DieHard on December 29, 2023, 09:58:42 AM
Hello, i have added a copper heatsink in my Mac Mini 1.92GHz

Wow, that looks gorgeous !   Can you please explain where you sourced that and if you had to modify it ?   What was the install process ?
Title: Re: Mac Mini G4 Overclock / HEATSINK!
Post by: aBc on December 29, 2023, 11:05:32 AM
Indibil does it AGAIN!

GREAT WORK!!!

He says:
“…now the fan blows more slowly, as it did with the original CPU at 1.25GHz, and the air feels hot. Before changing the heatsink the fan was blowing faster (@1.92 GHz) and the air coming out quickly did not seem to be as hot, although it was.”

My question is - what is the exhaust air temperature measured at the back case opening NOW with the new heatsink and slower fan speed? (Cold boot, no load, at idle…temps taken @10 minutes and @15 minutes?)

Suppose I should make similar copper heatsink for “stock” Mac minis here to check for possible measurable improvement?

We don’t need no stinkin’ CNC! ;)

https://rosysumenteinquieta.blogspot.com/2023/12/mac-mini-g4-192ghz-con-disipador-de.html
Title: Re: Mac Mini G4 Overclock / HEATSINK!
Post by: teroyk on December 29, 2023, 11:37:51 AM
Suppose I should make similar copper heatsink for “stock” Mac minis here to check for possible measurable improvement?

And/or big "hot rod" copper heatsink for tests that would be possible make fanless 1.0 Ghz Mac Mini.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on January 01, 2024, 11:33:19 PM
Hello, the heatsink is this:
https://es.aliexpress.com/item/1005004262614951.html?spm=a2g0o.order_list.order_list_main.96.58b1194d3UjeS7&gatewayAdapt=glo2esp (https://es.aliexpress.com/item/1005004262614951.html?spm=a2g0o.order_list.order_list_main.96.58b1194d3UjeS7&gatewayAdapt=glo2esp)

As it measures 50x50mm, I had to cut the width to leave it at 50x40. The height is the same as the original.

First you have to protect the base that have contact with the CPU, I used yellow thermal tape. Using the original as a template, you make the four 3mm diameter holes, and then with sheet metal scissors I cut out the fins in the area of the holes and patiently filed what was left.

I can't measure the temperature, I don't have any reliable thermometer right now, but with the original, and the Mini closed, it blew a lot, with this one, at 1.35v final, it doesn't blow excessively, but it's winter here, it's cold.

I take this opportunity to ask you for help. I have found 32MB VRAM chips like those used in the Mini 1.5GHz, and I would like to change them, but for it to be recognized, I would have to flash the ROM of the 9200 graphics card, but I cannot find any utility for "OSX PPC", nor can I locate in which EPROM it is stored. Maybe it's on the same EPROM as the Mini's BOOT ROM?

Surely there are experts

P.S. I don't know the VRAM speed set on the Mini, but the chips are 300MHz. GaphicAccelerator doesn't show my graphics card speed on the Mini.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on January 02, 2024, 04:34:03 AM
I have check with Aticcelerator II and the speed of the VRAM is only 190MHz, but the memory chips is rated 300MHz. It is for reduce temp or reduce consumption?

Rare...

Title: Mac Mini Video HELP?
Post by: aBc on January 07, 2024, 09:27:29 AM
Okay.
No one can offer any insights or possible help here for indibil?


I take this opportunity to ask you for help. I have found 32MB VRAM chips like those used in the Mini 1.5GHz, and I would like to change them, but for it to be recognized, I would have to flash the ROM of the 9200 graphics card, but I cannot find any utility for "OSX PPC", nor can I locate in which EPROM it is stored. Maybe it's on the same EPROM as the Mini's BOOT ROM?

Surely there are experts?

P.S. I don't know the VRAM speed set on the Mini, but the chips are 300MHz. GraphicAccelerator doesn't show my graphics card speed on the Mini.

Pretty please... and with some sugar on it?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on January 10, 2024, 07:16:40 AM
Well, it seems that no one is interested in the topic. Well, I bring you some progress. I confirm that it is necessary to flash the graphics card with the appropriate ROM, it does not automatically detect the 64MB. I have changed the VRAM and the image appears undefined. Tested with all 4 chips, to rule out defects. I have re-soldered the 32MB ones, and the image is back.

We need some ATIflash for Mac OS9 or OSX that allows us to download from 1.5GHz and load at 1.25/42GHz. Unless the ATI ROM is stored alongside Apple's Boot ROM, then you will need to dump that content and add it back. I have a TL866 programmer and adapter for that chip, but someone should desolder and read the Boot ROM from their Mini 1.5GHz with a programmer.

edit: It is possible that the 32MB chips instead of the 16MB ones did not work because the original ones are HY5DU283222AF at 2.5V and the ones I put in from the PowerBook are HY5DS573222AF at 1.8V. Perhaps that excess voltage has caused the incorrect operation. Difference between "DU" and "DS", I just noticed the difference.

edit 2: There were some minor graphical glitches, and I thought that by reflowing they would be solved, but my surprise was that after the reflow with the two 16MB chips I now have the same symptoms as with the 32MB chips!! Those 32MB chips came from a motherboard for parts, and perhaps they were damaged, or were damaged when removed, due to excess heat. Soldering memory chips costs much more than a CPU. Now I have found both 16MB and 32MB used chips, but they will take a few weeks to arrive. I have to find out the VRAM voltage because the 32MB ones are still 1.8V and the 32MB ones are 2.5V. Both 300MHz. I would be grateful if someone could provide me with the schematic of the Mac Mini G4: 820-1652-A, because I can't find it.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on January 10, 2024, 11:26:31 PM
The ideal would be to find Hynix HY5DU573222F that operate at 2.5V like the original Hynix HY5DU283222F. In the PB there was only HY5DS573222F and on ebay I have only found HY5DS573222F, so to be able to use 64MB of VRAM with those chips it is necessary to lower the VRAM voltage from 2.5V to a maximum of 2.1V. They support a maximum of 3.6V but it is not optimal. I attach screenshots.

I need Mini G4 schematics.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on January 12, 2024, 09:42:49 AM
I need the schematics of the Mac Mini G4 for two reasons, first to be able to change the VRAM voltage from 2.5V to 1.8V, although I have a plan B that also requires the schematics.

The other reason is because in the schematics of the iMac G4 I have seen that there are some resistors that by combining 0 and 1 you can choose between the type and amount of VRAM installed, and perhaps the Mini has something similar. If I manage to install the 64MB ones, it may only recognize 32MB without this change.

I mention this in case anyone is interested in joining the project and moving forward.
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: Greystash on January 12, 2024, 11:24:54 PM
I've had a decent search but haven't been able to find anything sorry. Have you tried asking at 68kMLA?
Title: Re: Mac Mini G4 Overclock just because its fun.
Post by: indibil on January 12, 2024, 11:42:43 PM
Thanks for your help. :)

I've asked a few questions on 68kMLA but don't usually get a response.