World's Fastest iMac G4 - 2 GHz iMac G4 CPU Upgrade

[caincha]

I decided to buy a A1106 logic board @1.67ghz stock and just go with that since this one didn't work well.

The reason I'm thinking my overclock failed is because I'm just using tin solder to jump connections that were intended to be done with a resistor - and that might be why it works on Safe Boot but won't boot properly…

I am also considering to buy another SSD and put it on the DVD drive to RAID the thing but I can't find a caddy for the PowerBook does that even exist - and if not is there any adapter available that I could use?

I would like to point out that with the exception of the SSDs everything else is coming very cheap plus I am enjoying this project - would enjoy more if I could overclock it but anyway… So the thing is I'm not expending that much money on it and it is mostly for fun not to be like some PPC fanboys out there

 

[AphoticD]

The reason I'm thinking my overclock failed is because I'm just using tin solder to jump connections that were intended to be done with a resistor - and that might be why it works on Safe Boot but won't boot properly…

From experience with overclocking my Macs, the PLL resistors are 0 ohm, as in equivalent to a tin solder blob or wire. I’d say the fact that it safe boots is more likely a GPU related issue. Is there any correlation between the CPU core voltage and GPU voltage or frequency?

 

[caincha]

From experience with overclocking my Macs, the PLL resistors are 0 ohm, as in equivalent to a tin solder blob or wire. I’d say the fact that it safe boots is more likely a GPU related issue. Is there any correlation between the CPU core voltage and GPU voltage or frequency?

At the top of my head all I can remember is that the vCore can be done with tin solder - zero resistance - but the PLLs should be using a resistor. Would have to double check the schematics though...

If it is zero resistance as well then I can only think of 2 things:

1. Instead of jumping just one of the PLLs resistors I might try jumping all 3 of each. Failing that then:
2. This particular board is not overclock-friendly so I’ll give up and swap with the A1106 board @1.67ghz.

Oh and the GPU was working flawless before so I don’t think there’s a issue there. Also everywhere I read about PowerBook O/C I haven’t seen any mention about it being a issue.


As for the RAIDing issue I noticed both the HDD and DVD connectors look the same on the board. As soon as I get my hands on another HDD ribbon I’ll check if that turns out to be true or not.

If so that solves the issue of finding a DVD caddy - which seems next to impossible for such a old laptop...


Also which would be the most compatible Linux for this PowerBook? One that runs all the devices or at the very least the wi-fi right ‘out of the box’?

I might try a PPC distro if I want it to be fully usable on 2018 as OSX seems like it won’t do much with very old software specially on a web browser...

 

[caincha]

Yeah it seems it's zero resistance. 10k resistance would be something else close by which confused me…
Anyway I'll try this: it seems there really are the right ones to jump for it to work properly so I'll try this next. If it works @1.83ghz I'll try @2.00ghz again just to be sure if it works or not.
If nothing works I'll just swap for a stock 1.67ghz logic board and get over this - for now anyway. Try to find a Linux distro that I like before I get bored with this project

 

[caincha]

Dual drive unsuccessful so far…
Logic board connectors look the same:

And so does the ribbon connections - even the numbers are the same:

But the screen remains black if I try to boot 2 drives at the same time (all components tested and working properly).
At first I thought it could be a power limitation (maybe the DVD requires less power than a HDD I don't know but I had this issue on my iMac) so I tried the SSD and it still wouldn't boot - screen turns on but remais black and no chime.
Then I thought it couldn't be power limitation as I saw on YouTube someone booting RAID HDDs using a caddy so what can I be missing here…?

 

[AphoticD]

I understand they are on separate connectors, but perhaps you could try disabling "cable-select" and set the drives as master and slave manually? They could be sharing the same logical bus.

 

[weckart]

Looking at the logic board, at the optical drive connector J13 appears 2/3 towards the end whereas J12 is at the end of the HDD connector. Are they wired up differently? Just wondering if you flipped the optical drive and HDD, whether that would still boot up.

 

[caincha]

I understand they are on separate connectors, but perhaps you could try disabling "cable-select" and set the drives as master and slave manually? They could be sharing the same logical bus.

That could work and I know how to do this on a PC but how do you do it on a OSX laptop…? There's no BIOS to change the settings…
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Looking at the logic board, at the optical drive connector J13 appears 2/3 towards the end whereas J12 is at the end of the HDD connector. Are they wired up differently? Just wondering if you flipped the optical drive and HDD, whether that would still boot up.

No that's the right way to plug it. The writings are upside down for whatever weird reasons they had when manufacturing it…
But I did had the same idea as you and tried that before reading it here and it didn't work anyway

 

[AphoticD]

That could work and I know how to do this on a PC but how do you do it on a OSX laptop…? There's no BIOS to change the settings…

Do your hard drives have a jumper block? I imagine you should be able to set the jumper pins accordingly.

 

[caincha]

Do your hard drives have a jumper block? I imagine you should be able to set the jumper pins accordingly.

I’m using SSDs that’s why I couldn’t understand your suggestion as they don’t have jumpers...


I thought that there was something wrong with that.

 

[LightBulbFun]

if you want to Dual HDD a PowerBook

your best off just getting a OptiBay type device, rather then faffing around with Logic-board cables

but for what its worth most mSATA 2.5 inch IDE adapters do generally have CS/Slave/Master jumper blocks on them.

 

[weckart]

That could work and I know how to do this on a PC but how do you do it on a OSX laptop…? There's no BIOS to change the settings…
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No that's the right way to plug it. The writings are upside down for whatever weird reasons they had when manufacturing it…
But I did had the same idea as you and tried that before reading it here and it didn't work anyway

No. That's not what I mean. I am talking about the actual jumper point markings on the logic board. The cable connectors look identical but the logic board wiring might differ and it may have something to do with Master/Slave/Cable Connect. When I mean flip the the optical drive, I mean attach the DVD drive to the HDD connector on the left and the HDD to the optical port on the right. Or is that what you meant when you said you tried it already?

 

[caincha]

When I mean flip the the optical drive, I mean attach the DVD drive to the HDD connector on the left and the HDD to the optical port on the right. Or is that what you meant when you said you tried it already?

No the DVD is still screwed in. What I did was to go back and forward with the SSD/HDD on those connectors.
Another thing I tried - since I now have 2 logic boards and 0 F to give - was to hot plug both. The DVD kinda works but the HDD freezes the system and that was with the board on stock clocks.

And about clocks once I realised my other logic board was also 1.5ghz I stopped caring and O/C that one as well this time following the schematics regarding which resistors to jump on each PLL. Turns out that doesn't work either.
And now that I have tried different methods and both didn't work I'm considering abandoning the O/C idea and focus on making the RAID work. If I can't make that work I might just abort the project altogether I don't know…
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but for what its worth most mSATA 2.5 inch IDE adapters do generally have CS/Slave/Master jumper blocks on them.

A 2.5" SSD won't fit even with the smallest adapter so I got a 1.8" SSD which doesn't have any jumpers.

 

[Bug-Creator]

Regarding that PowerBook, did some similar experiments with a 5.8 recently.

Foil-cable -> to some HDD-caddy converting to SATA -> SATA-extension -> SATA to miniSATA -> slim SATA-DVD : works
Foil-cable -> to some HDD-caddy converting to SATA -> SATA-HDD : boots 2nd HD visible
IDE(HDD)-port -> SATA-> miniSATA ->slim SATA-DVD : OSX-DVD boots but fails to see the HDD as an install destination (MorphOS CD hangs at splash screen).

 

[CooperBox]

There's certainly a lot of very useful information here, but imo it's a pity that post #35 was not raised as a new thread, specifically for overclocking the A1106 1.5ghz PowerBooks.
As the subject title 'World's fastest iMac G4 2GHz upgrade' particularly interests me, the last 20+ posts although informative, have a tendency to cause confusion for those reading for specific iMac G4 upgrade info - myself included.
It's possible that others in the future may have specific info to share on A1106 PowerBook upgrade, but due to the thread title, not look in and walk past.
Just a thought on the possiblity of merging posts #1-#34, and posts #35 thro #64 into two separate threads.

 

[caincha]

My thought was that if anyone overclocked the iMac PPC there might have some knowledge to share about other PPCs like the PowerBook.
Not against merging into another thread though - just message a moderator and ask

 

[DearthnVader]

BTW, @dosdude1 setting HID1 bit 9 should allow DFS mode with your 15x multiplier reducing to 7.5x.

Can be set with ReggieSE from CHUD Tools.

ReggieSE is scriptable, so you could create a command script to set/unset bit 9.

Setting bit 17 of the fifth 32bit word for the PRIM_INFO may allow the Processor performance option to be available in the Energy Saver Control Panel.

 

[ks23]

@dosdude1

Regarding MPC7448, I would ask NXP if they could give you some CPUs for free. I would also tell them about your project. Maybe you're lucky.

FreeScale then advertised the MPC7448 as a drop-in replacement for the 7447.

GigaDesigns, PowerLogix, NewerTech, FastMac also offered CPU upgrades with 7448.

So should "actually" be no problem to get Macs running with 7448. Firmware should be available for this.
https://www.macintoshrepository.org/8007-powerlogix-newertech-g4-enabler

Would be great, if Powerlogix goes OpenSource regarding the CPU upgrade-cards

 

[dosdude1]

@dosdude1

Regarding MPC7448, I would ask NXP if they could give you some CPUs for free. I would also tell them about your project. Maybe you're lucky.

FreeScale then advertised the MPC7448 as a drop-in replacement for the 7447.

GigaDesigns, PowerLogix, NewerTech, FastMac also offered CPU upgrades with 7448.

So should "actually" be no problem to get Macs running with 7448. Firmware should be available for this.
https://www.macintoshrepository.org/8007-powerlogix-newertech-g4-enabler

Would be great, if Powerlogix goes OpenSource regarding the CPU upgrade-cards

I'm not sure you saw, but I actually did get a 7448 running perfectly in an iMac G4. That post is a couple pages back, found here.

I'm not sure that NXP would provide me any free processors LOL, especially considering they're still selling for over $300 on Mouser. I suppose I could ask, though...

 

[ks23]

Ah sorry. I didn't saw it.
You would be surprised what you could get for free from NXP, if you ask
Yes, the 7448 is terrible expensive compared to e. g. T2080 ...

e2v also sells the 7448, but I assume to an even higher price:
https://www.teledyne-e2v.com/products/semiconductors/processors/

And Powerlogix said back in 2006, they will develop an G4 upgrade based on a MPC8610/ 8640. But it never appeared.

Anyway, good work from your side.

 

[ardweebno]

I'm not sure you saw, but I actually did get a 7448 running perfectly in an iMac G4. That post is a couple pages back, found here.

I'm not sure that NXP would provide me any free processors LOL, especially considering they're still selling for over $300 on Mouser. I suppose I could ask, though...

For what it is worth, this seller on eBay has MPC7447B1667 devices on sale for $9.50/each. The item description says it is a 667 MHz part, but the datasheet and the picture say it is a 1.67GHz device.

 

[Zachsch22]

Sorry to revive an older thread, but I just acquired some G4’s and have a few questions about modifying them and was wondering if dosdude1 was still around and offering his upgrade services

 

[Jubadub]

Holy sh!et, I didn't see this thread before. Amazing!

This got me inspired to look again at my 1.5GHz Mac mini G4 to carefully see how I can improve its cooling so I can safely clock it to 2 GHz, as well. Thanks to the MacOS9Lives community, the mini also runs 9.2.2 natively. So this has to happen!!! It's WAITING for it to happen! It's possible already! Now comes the "how"!

 

[Amethyst1]

This got me inspired to look again at my 1.5GHz Mac mini G4 to carefully see how I can improve its cooling so I can safely clock it to 2 GHz, as well.

IIRC @LightBulbFun got his 1.5 GHz G4 mini to run at 1.67 GHz so you could use that as a starting point. And yeah, let's build a watercooled mini

 

[Appleuser201]

Well, after a lot of research and a good bit of info from @LightBulbFun, I finally managed to pull off something I've been working on for quite some time now... Making the world's fastest iMac G4. Back in the day, a company called "DayStar" used to perform such an upgrade for people, installing a G4 CPU (speculated to be a 7447), and clocking it to 1.92 GHz. Well, I thought I could do better, and indeed I have.

Let's start with the CPU. I decided to go with a 1.67 GHz MC7447B CPU, taken from a 15" PowerBook G4 logic board. Not only are these CPUs much cooler-running than the stock MC7445 CPUs used on these model iMac G4s (1.0 - 1.25 GHz models), but they also, obviously, have a higher rated clock. This means, that with the thermal capacity of the iMac G4's cooling system, we should be able to get a decent overclock out of it. The iMac G4 board also supplies the CPU VCORE rail with around 1.5V, which is just perfect for a 7447.

Now, the main issue I ran into: Firmware. As I found out (the hard way), a system firmware patch is required in order for the system to be able to boot with a 7447 CPU installed. I didn't realize this, and went ahead and soldered one onto my 1.25 GHz 17" iMac board. Of course, the board would no longer POST afterwards. Fast-forward quite a few months, though, and @LightBulbFun comes in with a solution: A firmware patching utility, designed for use with Giga Designs CPU upgrade cards for use in certain PowerMac G4 models. Since my iMac was no longer working, I couldn't actually test it, but luckily I had a spare board from a slightly less powerful 1 GHz model iMac G4 (which also only had USB1.1 support and a worse video card). Even though this was not the board I was hoping to upgrade, I figured what the heck, and proceeded to run the firmware patcher on the machine. To my amazement, the firmware patch completed successfully!

View attachment 768625

In my excitement, I got to work immediately reballing a 7447, desoldering the original 1 GHz 7445 from the board, and finally soldered the 7447 onto the board. I then hooked the board back up to the system, turned it on, and it POSTed!

Lastly, I needed to set the PLL configuration resistors on the board to get the CPU clocked up to my target 2 GHz clock speed. Based on the schematic for the board, some info from @LightBulbFun, and a guide I found online, I set the PLL configuration appropriately (15X multiplier @ 133 MHz bus speed), assembled the machine, and proceeded to run some stress tests. It worked 100% the entire time, and seemed to run relatively cool as well. I would definitely consider this a successful upgrade, and I now indeed have the world's fastest iMac G4! My Geekbench result can be viewed here.

Now that I successfully completed this upgrade, I can now offer it as a service to anybody located in the US. If you are interested, please feel free to PM me!

View attachment 768627 View attachment 768628 View attachment 768629 View attachment 768630 View attachment 768631 View attachment 768632 View attachment 768633

So now with that 2ghz upgrade, TenFourFox can finally play YouTube well?
Just kidding...
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Holy sh!et, I didn't see this thread before. Amazing!

This got me inspired to look again at my 1.5GHz Mac mini G4 to carefully see how I can improve its cooling so I can safely clock it to 2 GHz, as well. Thanks to the MacOS9Lives community, the mini also runs 9.2.2 natively. So this has to happen!!! It's WAITING for it to happen! It's possible already! Now comes the "how"!

Post a pic of the Mini running 9.2.2
A Mini from 2005 running a OS from 2001