I was wondering if you've had any luck with this? It would be cool to get this mini out of 'limp' mode.
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"fastest" flash, and using a pencil to overclock.
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I was wondering if you've had any luck with this? It would be cool to get this mini out of 'limp' mode.
I see no reason why it wouldn't, considering the machines are identical other than the slightly faster CPU in the 10,2.
Don't know if I should bump the post, but ah well.
I have a 2005 eMac running at 1.92GHz with the vcore set to 1.375V on a 7447B. Not sure if my ROM will indeed support a 7448 but I would like for someone to try installing one on my board for me someday. I think the 1.7GHz 7448 could potentially get to 2.2GHz. The computer has ran rock solid for over a year now, but I feel like I am pushing this 7447B a little too hard. Not sure if dosdude1 has a service for putting a 7448 in, but it would be freakin' epic.
The ROM on this computer is version 4.9.2 and I have not dumped it just yet.
I have a 2005 eMac running at 1.92GHz with the vcore set to 1.375V on a 7447B. Not sure if my ROM will indeed support a 7448 but I would like for someone to try installing one on my board for me someday. I think the 1.7GHz 7448 could potentially get to 2.2GHz. The computer has ran rock solid for over a year now, but I feel like I am pushing this 7447B a little too hard. Not sure if dosdude1 has a service for putting a 7448 in, but it would be freakin' epic.
The ROM on this computer is version 4.9.2 and I have not dumped it just yet.
I think the first steps would be to see if any of the firmware patches work on that computer. If so, then try the nvram script (this step does not work on the mini). If that all works, then it would be a matter of obtaining a 7448 and soldering it onto the pcb. I can do the soldering, but finding an affordable 7448 is tricky.
from what we have seen Apple BootROMs of the 4.9.x range have native 7448 support although I recommend dumping your BootROM and sending it to @dosdude1 so he can check that
in a somewhat ironic twist, this sadly means although a 7448 may well work OOB, it means OS X wont boot, since
when you have a BootROM that does not support 7448's you patch it and then theres a secondary NVRAMRC script to further get OS X to boot on a 7448, but this Script does not work when the BootROM has native support for a 7448
im hoping at some point someone can either figure out how to get the script to work with natively supporting BootROMs or Patch the OS X kernel to natively support the 7448
(I do wonder what Daystar did for their 7448 DLSD's since the BootROM of a DLSD natively supports a 7448)
I do agree a 7448 in an eMac would be quite fun to see especially given their robust cooling system I think you could overclock one quite nicely to 2Ghz if not more
I think the eMac's PLL allows for 800MHz to 2.08GHz if I recall correctly. I would love to get it to break the 2GHz barrierfrom what we have seen Apple BootROMs of the 4.9.x range have native 7448 support although I recommend dumping your BootROM and sending it to @dosdude1 so he can check that
in a somewhat ironic twist, this sadly means although a 7448 may well work OOB, it means OS X wont boot, since
when you have a BootROM that does not support 7448's you patch it and then theres a secondary NVRAMRC script to further get OS X to boot on a 7448, but this Script does not work when the BootROM has native support for a 7448
im hoping at some point someone can either figure out how to get the script to work with natively supporting BootROMs or Patch the OS X kernel to natively support the 7448
(I do wonder what Daystar did for their 7448 DLSD's since the BootROM of a DLSD natively supports a 7448)
I do agree a 7448 in an eMac would be quite fun to see especially given their robust cooling system I think you could overclock one quite nicely to 2Ghz if not more
It should be possible with 7447A rated with 1667 MHz, maybe watercooled only.
I still have my 1.92 GHz eMac and I'm tempted to dig it out, put WC on it and try.
On air it crashed @2.0 GHz AFAIR, it was years ago.
Hell, I must dig it out. While posting this I found my old post from 2010 where I wrote that mine has 7448 CPU. I must check if I was mad or stoned these days or it's really true...
Edit: OK, I was stoned presumably Found another post from these days where I corrected myself: 7447B it was (and still is).
I still have my 1.92 GHz eMac and I'm tempted to dig it out, put WC on it and try.
On air it crashed @2.0 GHz AFAIR, it was years ago.
Hell, I must dig it out. While posting this I found my old post from 2010 where I wrote that mine has 7448 CPU. I must check if I was mad or stoned these days or it's really true...
Edit: OK, I was stoned presumably
Found another post from these days where I corrected myself: 7447B it was (and still is).
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I'm not sure this is a direct correlation. For example, has anyone tried the script on a DLSD? I tried it on a Mini 10,1 and it does the same thing as on a Mini 10,2.
The legend returns!
Your old post gave me the idea to test the OC to begin with. Still rock solid after all these years! Also no eMac (and no stock mac) ever used the 7448. The 2005 eMac uses a 7447B.
the min/Max clock speed/PLL settings are down to the CPU
all you need to do is find the appropriate PLL resistors!a 7448 has a max multiplier of 28 so you which gives you a max theoretical clock speed of 4.6Ghz given the 166Mhz bus of an eMac
you might need some liquid helium and a VRM upgrade for that mind LOL
interesting that it also "bricks" the 10,1 as well, I must of missed that, its good to know, but also interesting
as I know the script worked on a PowerBook6,8, I think some more testing is needed!
Oh god, a 4.6GHz eMac... The eMac already has some beefy VRM but I think it may only get up to 2.2GHz, maybe even 2.4. Usually I only have luck when the chip is clocked 500MHz above the original speed. Now to find someone who has a 7448 and can swap it into the eMac. Will need to do some checking first. What linux distro should I use for flashrom?
the min/Max clock speed/PLL settings are down to the CPU
a 7448 has a max multiplier of 28 so you which gives you a max theoretical clock speed of 4.6Ghz given the 166Mhz bus of an eMac
BRB pricing how much a compact, liquid nitrogen-cooling system for a DLSD 17-inch PowerBook (you see, it has more room inside… something like that) costs…
At long last, I finally had some time to test out a Mac Mini G4 7448 CPU upgrade with my patched BootROM. Of course, I used a PowerMac10,1 for my testing, as a PowerMac10,2, as we discovered, does not require any BootROM patches. This, however, is where I ran into an issue. While my patched BootROM works perfectly, the NVRAMRC script needed to boot a stock OS X kernel does not... It simply causes the machine to do nothing but chime, and then sit there doing nothing. Exactly what happened when @ervus attempted on his unpatched PowerMac10,2 system with 7448. So, this script definitely needs to be modified in some way to make this a useful upgrade, with the ability to boot OS X with full CPU support and an unmodified kernel. My theory is that something about the OpenFirmware in this later BootROM version is different, or it could be relying on some sort of offset in the firmware binary itself. Unfortunately, I'm not very familiar with Forth or FCode, but I will see what I can figure out. Any help would be appreciated.
Could someone with a DLSD try the script?
Otherwise, DearthnVader seems to know some fcode stuff.
HUGE UPDATE! The FCode binary is NOT THE ISSUE!!! It's simply something with the other parts of the NVRAMRC script, or something to do with the way NVRAMRC is executed in these newer BootROMs. Executing the FCode manually using the boot command in Open Firmware WORKS, and I was able to boot OS X no problem with the 7448 in the PowerMac10,1!!! The binary file to execute is attached, it can simply by executed using:
"ud" may need to be devaliased first for a USB drive, and "3" is the partition on a USB drive. You could load from internal HDD as well.
Then the system can be booted successfully using mac-boot!
Code:
boot ud:3,\FCode.bin"ud" may need to be devaliased first for a USB drive, and "3" is the partition on a USB drive. You could load from internal HDD as well.
Then the system can be booted successfully using mac-boot!
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So I can get the FCode.bin file to load in OF, but as before OS X won't boot (linux and modified OS X kernel still do).
It looks like FCode.bin populates the nvramrc setting, but not the use-nvramrc? setting. If I set this to true, then it bricks it as before.
Are you doing this for every boot, or just once?
It looks like FCode.bin populates the nvramrc setting, but not the use-nvramrc? setting. If I set this to true, then it bricks it as before.
Are you doing this for every boot, or just once?
thats pretty bloody awesome you managed to get something working!
I really look forward to seeing the holy grail of a 7448 DLSD at long last
and I also personally want to see a 7448 installed onto a 1.42Ghz eMac and I am curious if all the 4.9.x BootROM G4's natively support the 7448, its certianly looking that way
which is pretty awesome, as although we have patches for older BootROM's, I dont know if when you boot Linux on those if the L2 caches are enabled etc, see OpenFirmware normally sets those up
but on an unknown CPU they are not setup, we are lucky that OS X is smart enough to set them up itself, but I dont know if linux etc is, so having native support is very nice!
I am also curious since we already know from you checking it that the DLSD's BootROM does support the 7448, I do wonder if the DLSD supports the 7448 specific DFS mode, where it divides the multiplier and such the clock speed by 4 when set to a round multiplier, I have long since theorised that this is why the DLSD's power saving preferences are different from all other PB's
Has to be done at every boot. If you "boot" the FCode bin successfully, it should say something like "evaluated fcode". Once done, just type "mac-boot", and let it continue booting. If you reboot after executing the FCode, its changes are gone.