I think either would probably work. You can try searching for PVR values in the firmware to maybe tell which are supported or blocked as described by joevt. It appears that the ZIF models can use 750F or 750G without modification, and these may be closely related to the iMac?
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PPC750GX vs. PPC750GL?
- Thread starter trag
- Start date
Probably the biggest difference between the 750F and the 750G is the bigger cache. This shows a memory test of an 800MHz 750G, and you can see that the cache is almost 20x faster than RAM:
...so depending on what software you're using a bigger cache can help a lot. Here is a geekbench test of an 800MHz iBook (750F) vs an 800MHz Pismo (750G) booted from the same external firewire drive:
...so maybe you could guestimate that on average a 750G would be around 7% faster than a 750F at the same clock. Plus maybe the 750G can clock higher. I've now tried several of the ebay batch of 750G chips and 1.1GHz seems to be their practical limit. I'm now running the Pismo at 1GHz and trying incrementally lower voltages to see if there is a nice low power setting.
...so depending on what software you're using a bigger cache can help a lot. Here is a geekbench test of an 800MHz iBook (750F) vs an 800MHz Pismo (750G) booted from the same external firewire drive:
...so maybe you could guestimate that on average a 750G would be around 7% faster than a 750F at the same clock. Plus maybe the 750G can clock higher. I've now tried several of the ebay batch of 750G chips and 1.1GHz seems to be their practical limit. I'm now running the Pismo at 1GHz and trying incrementally lower voltages to see if there is a nice low power setting.
The firmware patcher is "NewerTech ROM 3.1b5 joevt v2" in the Notes folder.
I've added the new CPU patch to the firmware patcher for 4.5.7f1, 4.6.4f1, and 4.6.5f3
4.6.4f1 is new to the firmware patcher. I was able to use the 4.5.7f1 firmware dump to find where to apply the patches in 4.6.4f1.
There's 4 patches. I don't know what they do. I only changed the CPU part of the hid0 patch.
- hid0 - contains the new CPU patch
- pll
- l3cr
- thermal
When you run the patcher in Open Firmware, it explains what each patch is for.
My patches have version 30f1. Original patches are 20f1 or earlier.
None of this is tested by me.
The patcher is
I've added the new CPU patch to the firmware patcher for 4.5.7f1, 4.6.4f1, and 4.6.5f3
4.6.4f1 is new to the firmware patcher. I was able to use the 4.5.7f1 firmware dump to find where to apply the patches in 4.6.4f1.
There's 4 patches. I don't know what they do. I only changed the CPU part of the hid0 patch.
- hid0 - contains the new CPU patch
- pll
- l3cr
- thermal
When you run the patcher in Open Firmware, it explains what each patch is for.
My patches have version 30f1. Original patches are 20f1 or earlier.
None of this is tested by me.
The patcher is
NewerTech ROM 3.1b5 joevt v2. I guess you run it like the original NewerTech patcher? It's a tbxi file so it should boot if it's in the blessed System Folder of an HFS or HFS+ disk?
indibil
Well-known member
Although I'm pretty decent at electronics, messing with firmware is difficult if I have to type commands. I don't like doing it without understanding what I'm doing.
The Newertech patcher I've used on some G4s has been a Newertech BootCD. I boot the G4 by pressing the programming button, and when it beeps, I hold down C and release the programming button. Then the Newertech CD boots and I patch from its menu.
How should I use this patcher?
But I'm still wondering about the BGA pattern of both. A PPC750FX doesn't seem compatible with the pattern of a G3 on an iMac Tray or Pismo; that BGA pattern is similar to that of the MPC7400.
I've been reading the thread and I don't quite understand how to do it.
indibil
Well-known member
No había visto esta foto, hiciste un intercalador. Eres brillante. Ese es mi problema.
You could duplicate the NewerTech BootCD and replace their tbxi file with mine.How should I use this patcher?
indibil
Well-known member
Perfect, thanks.
From what I understand, your patcher didn't remove anything from the original patcher; it's still valid for the 7447 and 7448, right? You only added the new G3s.
This way I can make a boot CD and save it as UNIVERSAL.
Thank you for the work you have all done; it's a shame I don't have interposers.
Correct. I have not tested anything though. I've included all the code which shows what gets changed. You can save your firmware, do the patch, and save the new firmware to compare. I can do the compare for you. Assuming you can still use your Mac
Daniël
Well-known member
FYI, their webshop has better rates for international shipping, the only option on eBay is ludicrously expensive to mainland Europe:
www.zombiecomponents.com
Lot Of 10 Each IBM Ppc750glecr2h33v-G Powerpc 32-Bit 800 Mhz Risc Processor - ZOMBIE COMPONENTS
Store policies:
www.zombiecomponents.com
LightBulbFun
Well-known member
very cool to see you got this working! in some regards a full replica of the old PowerLogix 750GX Pismo upgrade
did you ever manage to get the 7447A/7448 working with your interposer on the Pismo cards?Did any of the Powerlogix Pismo G3 upgrades use the 750G? ...or were they all the 750F? I used the firmware and mach_kernel patches from joevt to get the 750G working. I think a 750F would work without either. I don't remember hearing about patches for this stuff from Powerlogix, so maybe they only used "F" chips or else found a different way to fix or trick the firmware? Am I the only one who has tried asking OWC about these things? Maybe with some sort of crowd funding they would sell all of the design info for public release.
I only tried the 7447 in a Pismo once (as described in that other thread) and the fact that the joevt patches work for the 750G suggests that the problem was in the wiring (not the software). I did notice a few differences in the Pismo vs the CPU boards for the tower computer series. If there is interest I could find another Pismo donor board and take another look. On the 750G I used some resistor packs directly on the adapter to control some of the pins, instead of reverse engineering the apple host board and relying on however that was done. At least this makes it interchangeable between the Pismo and AGP machines.
I only tried the 7447 in a Pismo once (as described in that other thread) and the fact that the joevt patches work for the 750G suggests that the problem was in the wiring (not the software). I did notice a few differences in the Pismo vs the CPU boards for the tower computer series. If there is interest I could find another Pismo donor board and take another look. On the 750G I used some resistor packs directly on the adapter to control some of the pins, instead of reverse engineering the apple host board and relying on however that was done. At least this makes it interchangeable between the Pismo and AGP machines.
LightBulbFun
Well-known member
yeah the last of the PowerLogix BlueChip Pismo upgrades used 750GX's on interposers,
earlier ones did use 750FX's which you can see a physical example of here
either types would of needed Firmware patching, as I am pretty sure the Pismo has no Firmware support for the 750FX...
but this leads into the mistery of the 750GX ZIF, I had one of those briefly to play with, and I dont know how, but somehow PowerLogix was able to make it work in a G3 Beige or Blue and white, while having it pretend to be a standard 750, without the need for *any* Firmware or OS patches, I always wondered how they did that, especially with how simple the ZIF's where, they had no major IC's or CPLD's or FPGA's or anything like that! been a real head scratching mystery for me for many years now!
but sadly they set the default PLL mode to a 5x multiplier (in the G3 blue and white) so you *needed* software to kick it to full speed, except that software got broken in later versions of tiger.... I have always lemmented the PowerLogix 750FX/750GX upgrades for working like that! being default slow, because also means if your running alternative OS's your SOL there since there was never any powerlogix CPU software for OS X Server 1.2v3 for example
Powerbase
Well-known member
Yeah, my dad and me both had 1GHz GXed B&Ws. I don't remember doing a firmware update either and the boards were fairly simple. They didn't even bother putting any model numbers or anything on them.yeah the last of the PowerLogix BlueChip Pismo upgrades used 750GX's on interposers,
earlier ones did use 750FX's which you can see a physical example of here
either types would of needed Firmware patching, as I am pretty sure the Pismo has no Firmware support for the 750FX...
but this leads into the mistery of the 750GX ZIF, I had one of those briefly to play with, and I dont know how, but somehow PowerLogix was able to make it work in a G3 Beige or Blue and white, while having it pretend to be a standard 750, without the need for *any* Firmware or OS patches, I always wondered how they did that, especially with how simple the ZIF's where, they had no major IC's or CPLD's or FPGA's or anything like that! been a real head scratching mystery for me for many years now!
but sadly they set the default PLL mode to a 5x multiplier (in the G3 blue and white) so you *needed* software to kick it to full speed, except that software got broken in later versions of tiger.... I have always lemmented the PowerLogix 750FX/750GX upgrades for working like that! being default slow, because also means if your running alternative OS's your SOL there since there was never any powerlogix CPU software for OS X Server 1.2v3 for example
I think Mach Speed Tools could set the PLL on 750GXes and didn't get broken by the 10.4.9+ updates... I think. I didn't update as quick either because I had to wait for the Quartz Extreme enabler to be updated before updating too.
croissantking
Well-known member
I’ve never seen a 750P - is it the same as a 750L?
LightBulbFun
Well-known member
750P is Motorola's later version of the 750A, its die shrunk and runs at a lower core voltage
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