PowerBook G4 - 7448 or overclock 7447A

rabidz7

[H]ard|Gawd
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How much faster is a 7448 running at 2.2GHz/1.4v through a 200MHz but than a 7447A running at 2.0GHz/1.5v with a 167MHz bus? How much battery life would be saved by going with the 7448? I am trying to decide whether to overclock the current CPU or to have a new one soldered in. Please don't suggest a X86 laptop. I don't want one of those things.
 
You know, an Intel Bay Trail single core probably is just as fast as that thing, mostly due to the piss-poor bus bandwidth. A Bay Trail quad-core would absolutely manhandle it, and those are dirt-cheap. You're going to find it hard to find anyone with much interest in hacking those old things.

Why are you so fixated on PPC? Want to stroke your Big Endian? :D
 
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At the system level, probably less than 10% faster.

If you can even find the parts and someone to do the disassembly, system board PLL reconfiguration and reflow on a new CPU on the board (G4 systems often used resistor configurations for bus/CPU multipliers), what's the point? The last OS X version it can run is 10.5 (last system update: > 5 years ago), and you can run Linux on something much better than what it would cost to upgrade that laptop. I would be surprised if you could find someone to put in a new 7448, excluding the cost of the overpriced 7448 chip itself, for less than $300.

If you want more performance, just sell that one and get an x86 laptop. It will be more useful than that boat anchor. :p If you feel you must have a G4 for whatever reason, get a PowerMac G4 which are dirt cheap on Craigslist.
 
At the system level, probably less than 10% faster.

If you can even find the parts and someone to do the disassembly, system board PLL reconfiguration and reflow on a new CPU on the board (G4 systems often used resistor configurations for bus/CPU multipliers), what's the point? The last OS X version it can run is 10.5 (last system update: > 5 years ago), and you can run Linux on something much better than what it would cost to upgrade that laptop. I would be surprised if you could find someone to put in a new 7448, excluding the cost of the overpriced 7448 chip itself, for less than $300.

If you want more performance, just sell that one and get an x86 laptop. It will be more useful than that boat anchor. :p If you feel you must have a G4 for whatever reason, get a PowerMac G4 which are dirt cheap on Craigslist.

I have confidential Apple logicboard schematics for the laptop that list the resistors that control the bus clock, core voltage, and bus-core ratio. There is a BGA rework facility in my city that will do the job. I will take the logic board out myself and have them desolder the old CPU and solder in the new CPU. They will up core voltage to 1.4, set the bus to 200MHz, and push the CPU as fast as it will go. If it has a severe detrimental effect on battery life, I will have them back the voltage down to 1.3v and lower the core clock a bit. I love my PowerBook and I just want a bit of a performance boost. I don't want to use a X86 chip; if I did want one, I would not be using the PowerBook now. I am a PowerPC fanboy. I don't want to support an inferior architecture that was able to beat out PowerPC because of stupid reasons, such as software support and Intel paying off OEMs. I have a "Sawtooth" PowerMac G4 that I have overlocked to 480MHz over a 120MHz bus that is used as an emergency back up PC and I have my "Cypher" PowerMac G5 that is my go-to desktop for anything other than gaming.
 
I have confidential Apple logicboard schematics for the laptop that list the resistors that control the bus clock,
Freescale makes those publicly available and there are web sites which show which PLL input is connected to which resistors on the PowerBook G4 motherboard, along with other groups of resistors for other things. No whispers are necessary.

Apple chose to switch to x86 because even the lame Pentium 4 was beating the G5, which were consuming upwards of 180W *each* (hence the water cooling) in the dual G5 towers. G5 never made it to laptops because heating pads don't work very well as processors.

While you may have bitterness over PPC losing to x86, it wasn't because PPC was superior in any way*. That's just a fact. :p

The problem isn't finding a place to remove and reball a new processor, it's the cost is just not worth it, especially for the minor performance bump. Moving from a 130nm processor to a 90nm processor might save some power, but the difference in speeds and possibly voltage could make typical usage power consumption a wash.

Your likely outcomes are 1) spend hundreds of dollars to get a minimal speed bump on a relic laptop, 2) something goes wrong, you spend hundreds of dollars anyways and wind up with a non-functional relic laptop or 3) see that it's a pretty pointless upgrade and save your money for something more worthwhile.

* a faulty CISC vs RISC point will probably be brought up. The "RISC" PPC had been gaining complexity for years, and couldn't seriously be called RISC in any sense but the ISA; the execution units were becoming as complex as in some "CISC" processors. Starting with Pentium Pro (1995) on the x86 side, Intel moved to decomposing the CISC instructions into simpler micro-ops for very RISC-like execution units. The lines are quite blurry and the whole CISC vs RISC argument has been moot for a while. I only mention this because when someone claims PPC was better they usually depend on Apple's marketing/Jobs' reality distortion field for information.
 
Freescale makes those publicly available and there are web sites which show which PLL input is connected to which resistors on the PowerBook G4 motherboard, along with other groups of resistors for other things. No whispers are necessary.

No sites showed the control resistors on any high-res or 17" PowerBooks before I bought the schematics.
 
Everyone is correct, You are pissing away money on this project.

Your time/effort ( would also be cheaper ) to pick up a x86 cpu and do a Frankenstein install of mac os.
 
Everyone is correct, You are pissing away money on this project.

Your time/effort ( would also be cheaper ) to pick up a x86 cpu and do a Frankenstein install of mac os.

No, for a PowerPC-based system, this is absolutely worth it.
It's his money, and he can do what he wants with it.

PowerPC still has quite a few uses, and while x86 has an exhaustive software and hardware array, PowerPC (among other architectures) are more than fun to work with and have many applications which can be used on them, specifically.

No RISC, no reward. ;)
 
Old thread and like all others I've read online on the same subject - overclock a Powerbook G4 - this one looks filled with hate for some reason...

What I want to do is to overclock a 1,67ghz PowerBook to the closest I can get to 2ghz using volt mod, fsb mod, gpu mod and even display mod to get something close to 90hz.

No I don't need to do it, but I want to. If it is to run OSX, Lubuntu or MorphOS (more likely) it ain't the point, the point is that I want to O/C my PB and have fun doing it, what's wrong with that..?

And yes I already have an Intel iMac i7 quad fully loaded (SSD, maxed RAM, the works), so can we skip all the nonsense of 'why' and get straight to 'how'? :)

Thank you :D
 
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Well it’s been a while since I’ve been following this thread - according to my join date its been over a year lol - and I finally got my hands on a decent 2005 A1106 low-res PowerBook 1,5ghz with the idea of overclocking it.


The plan is to use the multipliers and crank it up to 2ghz and up the vCore from 1.385V to 1.5V.

Apart from that I plan to use the ATIccelerator to overclock the GPU, replace the 75gb HDD with a 80gb SSD (microSATA to IDE converter) and glue copper shins on any MOSFET I can see using a mix of 2/3 thermal paste + 1/3 liquid epoxi glue - maybe even glue some shins on the existing heatsink...


The questions I have before proceeding with the hardware mods are:

-I don’t have access to any resistors at all much less something so tiny as the stock ones, what would happen if I change the multipliers using molten solder? I know it should be ok on the vCore but what about the multipliers..?

-Would it make any difference to up the FSB from 167mhz to 200mhz? And how it could be done a low-res Powerbook?

-If I do change the FSB would it make any difference replacing the RAM PC2700 with PC3200?


I guess that’s it for now.

Appreciate any help
 
I'm confused…
My PowerBook is 1.5ghz A1106 but it's CPU says MC7447B and it's written 7447A at the bottom.
25ps16v.jpg

1zm0703.jpg

vnyxb6.jpg


Seems I found the vCore
o5c4jn.jpg


And the PLLs
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No idea about the BUS though or which guide to follow: hi-res or low-res?
 
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Followed the low-res guide and it kinda worked:
f4lmqc.jpg


Hardware upgrades and mods:
Maxed RAM to 2gb
Got a 80gb SSD microSATA to PATA
ATIccelerator pushing the GPU 30% above stock
PLLs jumped from 9x to 11x = 1.83ghz according to the multipliers sheet
vCore jumped from 1.30v to 1.60v
Speakers from a 2013 MacBook Pro (bought for $5 so yeah I gave it a shot)
2zrgop0.jpg



Lots and lots of copper shins:
Used a few shins with MX4 to bridge the gap between heat sink and GPU that was previously filled with thermal pads
Glued shins on MOSFETS using epoxy glue (1/3) + MX4 (2/3)
Glued a few shins on the heat sink itself and used thermal pads to attach shins on the back of the CPU/GPU - don’t know if any of that would really help to keep temps low but I figure it can’t hurt...
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But the thing is: it only boots on safe mode otherwise it gets stuck on the boot screen and the wheel doesn’t spin.
And that’s when it boots at all sometimes it stays on the black screen beeping different codes - one, three, four times on each power on...
 
1.75ghz won’t boot at all and 1.67ghz boots on safe mode but gives back grey screen on regular boot.
Oh and none would boot the install disk.
 
How much faster is a 7448 running at 2.2GHz/1.4v through a 200MHz but than a 7447A running at 2.0GHz/1.5v with a 167MHz bus? How much battery life would be saved by going with the 7448? I am trying to decide whether to overclock the current CPU or to have a new one soldered in. Please don't suggest a X86 laptop. I don't want one of those things.

Chromebook.


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Raspberry pi is probably faster.
 
I now have a Google PixelBook. I may or may not get the new PowerPC notebook that is coming out soon.
 
You could try 1.65v or 1.7v, even if you don't mind crushing your battery life.
 
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