Hey that's not true.
(Do note that the above command is for my configuration - 2x1GB, 6x4GB - if you want something different you'll have to adjust it)
You have to check first if the module numbers are recognised though.
This is an OpenFirmware hack btw.
View attachment 2107775
It's not fully 32 because it needs at least 2 sticks of not 4 GB to boot the system (I have 2x1 - but you can in theory put 2x2 as well).
However the speed may be low (I'm not sure - they are 266 for me for the 4GB ones). You can check this info with:
dev /memory
.properties
It all came from here btw:
QA1099: Describes how to configure the Power Macintosh so less memory is recognized than is actually present.
developer.apple.com
It's a 64 bit offset - then 32 bit size. You basically need to query it first from .properties and add up the additional sticks.
You want to keep the offsets aligned though and and the size at maximum 0xF0000000 (you are losing like 0x10000000 bytes for each 4GB stick).
If you don't align them akin to my post - the system will crash after peeking past the original low capacity x2 sticks.
And overall I suggest learning Forth:
TN1061: Describes the Open Firmware User Interface, Forth and the Open Firmware language used in Apple products.
developer.apple.com
(But you can just use my command as well - I currently have an ramsc script in boot-command)
\ comment
Your extend ram command
boot sd0:,\\:tbxi
So it extends the ram and then it boots from whatever.
Your boot-command should be:
setenv boot-command boot sd0:,\ramsc
Where ramsc is the file you have put your script in.
NVRAMRC - doesn't work here. You need to do it after that.
And also if you have linux (and use unsupported OS X GPU) I suggest making 2 scripts - one without the boot in the end so you can easily source yourself and boot other OS from the OpenFirmware terminal if needed.
If you have any questions - do please ask but as I've stated in the beginning first post your
" dimm-info" get-active-property
.s
(Check the address here)
ffa322b8 400 dump
(Where ffa322b8 is from above)
This will tell you the ram models - check if they are correct.
TL;DR:
You boot from 2x <4GB sticks (on first 2 slots - which are the one closest to each other on both sides in the center) (hope that succeeds and you don't hear the telephone beep - you may need to try multiple times then - or buy Samsung sticks (or the same on as I have because they worked for me - models here (in the hex dump)-
https://forums.macrumors.com/threads/overclocking-the-g5-cpu.2363051/post-31622390 ))
Rest of the sticks are 4GB sticks.
You then have (preferably) a boot-command that runs a script on your disk which extend the registered ram and boot OS.
Then you (preferably) start compiling Webkit on all cores on Gentoo and test if it works (if it hangs and crashes (after you have exceeded your original low capacity sticks size) you probably haven't aligned the offsets and sizes).