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Only a guess: it was cheap.

Yeah, but a marginal increase in cost for a better GPU would be trivial, and considering prices of PowerMac or PowerBook, consumers likely be willing to pay a bit more and get a better product. But anyway, that is all in the past now.
 
Oh come on.
Maybe my words with regards to the 5200 were a bit harsh (I'm not usually a friend of hyperbole, so take them as irony if you wish ;)) but it is, indeed, not a very impressive GPU for more than one reason and it makes no sense to me at all that the supposedly inferior iBook got a more powerful, Core Image-capable GPU for its final refresh, even if it was limited by 32 MB VRAM and just a VGA output.
 
Maybe my words with regards to the 5200 were a bit harsh (I'm not usually a friend of hyperbole) but it is, indeed, not a very impressive GPU for more than one reason and it makes no sense at all that the supposedly "inferior" iBook got a more powerful, Core Image-capable GPU for its final refresh, even if it was limited by 32 MB VRAM and just a VGA output.

Which performs better IRL though, given VRAM difference in favor of PB?
 
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:


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:


(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).
So I ended up with

Code:
\ comment
" "(0000000000000000800000000000000100000000800000000000000180000000F00000000000000280000000F00000000000000380000000F00000000000000480000000F00000000000000580000000F00000000000000580000000F0000000)" encode-bytes " reg" property
" "(8000000080000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF)" encode-bytes " bank-sizes" property
boot sd0:,\\:tbxi

in /ramsc and used

Code:
setenv boot-device sd0:,\\:tbxi
reset-all

that did the trick.

For Linux, I put the ram extend commands in ofboot.b for Debian, OpenSUSE and Gentoo, which is thus loaded automatically in the boot picker.

Same difference all in all

BTW it is very likely that one is able to edit the erroneously reported "PC2-3200U-288" values (they actually run at PC2-4200 speed afaik) by changing " dimm-speeds", presumably by hex dumping the its values using " dimm-speeds" get-active-property then .s and <whatever is returned> dump as you indicated, and then change them all to the value that corresponds to PC2-4200U-444

Thanks again sasho648!

Cheers,
 
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I wonder if the OF hack could be used for the iMac G5 iSight to get the stick to display in ASP, or on other macs, e.g. the G5 DC with e.g. 1Gb sticks to boot to OF and then only 2Gb sticks manually inserted? Or the regular iMac G5, which has two DDR slots so 1Gb + 2Gb? Same for the PB G4 DSLD (2 PC2-4200 slots), even though there are reports that G4s can't address more than 2Gb (which must be a firmware or possibly OpenFirmware limitation as 4Gb falls within 32 bits, if it's an OpenFirmware limitation there's hope)
 
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I wonder if the OF hack could be used for the iMac G5 iSight to get the stick to display in ASP, or on other macs, e.g. the G5 DC with e.g. 1Gb sticks to boot to OF and then only 2Gb sticks manually inserted? Or the regular iMac G5, which has two DDR slots so 1Gb + 2Gb? Same for the PB G4 DSLD (2 PC2-4200 slots), even though there are reports that G4s can't address more than 2Gb (which must be a firmware or possibly OpenFirmware limitation as 4Gb falls within 32 bits, if it's an OpenFirmware limitation there's hope)

An OF hack doesn’t appear to be necessary.
 
I honestly have no idea. At the end of the day, just having 4GB work on them, even if ASP “misses” them, would seem to be good enough, yes?
For me by all means, however the devil is in the details for some people, and it was a simple fix on the Quad :)
 
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I don't know what ASP is.

In any case if you provide the information I've requested before for @pc297 I may suggest stuff.
 
On a similar note, has anyone ever tried more than 2Gb on the DLSD? Or are G4 macs forever doomed to 2Gb tops?

I was also wondering about Intel macs, anyone ever tried 4Gb sticks on the mini 1,1/2,1? Would rEFIt/rEFInd/OCLP have any in-depth control of hardware/firmware settings such as under OpenFirmware to enable such a mod as we did on the G5?
 
On a similar note, has anyone ever tried more than 2Gb on the DLSD? Or are G4 macs forever doomed to 2Gb tops?

I was also wondering about Intel macs, anyone ever tried 4Gb sticks on the mini 1,1/2,1? Would rEFIt/rEFInd/OCLP have any in-depth control of hardware/firmware settings such as under OpenFirmware to enable such a mod as we did on the G5?

There have been folks who’ve tried to test different scenarios with the DLSD, but those tests were halted when their DLSD’s logic board failed (not related to said testing). The work to get >2GB on DLSDs to show up after booting is, far as I can suss, incomplete and not definitive.
 
And has anyone tried an 8GB into a 4 slots G5 1.8? 8GBx2GB PC3200 maybe?
Not tried 2Gb PC-2700 DDR1 DIMMS (they are hard to find) but have been meaning to, however it probably wouldn't be 8Gb total as you would still need a pair of 1Gb DIMMS to boot to OF and apply the reg hack from there, so it would be 7Gb, which would already be something!

One other option would be to buy 2Gb DDR SO-DIMMS and DDR1 DIMM adapters
 
I have an assumption that you can pre-determine the memory configuration in nvram and only then replace the memory sticks with 2gb.
I don't know, we would need to ask a Forth expert; re nvram the best we've been able to do is to load a Forth script from disk that assigns 4Gb sticks (on a Quad) in the reg using setenv (since they are otherwise not recognised). The script uses the following commands (for e.g. a 2x2Gb+6x4Gb configuration):

" "(0000000000000000800000000000000100000000800000000000000280000000F00000000000000380000000F00000000000000480000000F00000000000000580000000F00000000000000680000000F0000000)" encode-bytes " reg" property

" "(8000000080000000FFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFF)" encode-bytes " bank-sizes" property

(the latter so that the 4Gb DIMMs are recognised in ASP)

So I guess that if one were to use 2x1Gb sticks +2x2Gb sticks on a G5 DP with 4 slots, those commands could then become e.g.:

" "(000000000000000040000000000000010000000040000000000000018000000080000000000000028000000080000000)" encode-bytes " reg" property

" "(40000000400000008000000080000000)" encode-bytes " bank-sizes" property

If anyone knows how whether it is possible to set this in nvram directly? Not sure as the documented options for setenv seem rather limited

Of course, it could also well be that 2Gb sticks are supported out of the box (they are on DDR2 models), but if they aren't, the above would be a start for the course of action to follow
 
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I don't know, we would need to ask a Forth expert; re nvram the best we've been able to do is to load a Forth script from disk that assigns 4Gb sticks (on a Quad) in the reg via setenv, as they are otherwise not recognised via the command (for e.g. a 2x2Gb+6x4Gb configuration):
Do you think no one has tried soldering 4 extra slots on a june 2004 1.8?
 
Not tried 2Gb PC-2700 DDR1 DIMMS (they are hard to find) but have been meaning to, however it probably wouldn't be 8Gb total as you would still need a pair of 1Gb DIMMS to boot to OF and apply the reg hack from there, so it would be 7Gb, which would already be something!

One other option would be to buy 2Gb DDR SO-DIMMS and DDR1 DIMM adapters
The maximum would be 6Gb on those models using the ramsc script -if it works at all on those machines-, not 7Gb, sorry! Having one myself, if I ever come up with 2Gb sticks, I'll let you know (if it ever falls back to a normal power mode - it regularly has long phases, i.e. weeks - whereby it's stuck on fans blowing at full power - they don't show up in hardware monitor for example when this happens, haven't been able to determine the exact cause, likely ambient temperature related and the northbridge needing repasting, but it regularly and randomly pops out of this mode, often after booting an OSX install DVD)
 
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Do you think no one has tried soldering 4 extra slots on a june 2004 1.8?
This is probably possible, however some extra resistors would likely need to be soldered in too - look for empty resistor pads around the DIMM slot pads. You would likely need a reflow station with a heating plate for the ram slots - too many pads for a single soldering iron! Might be easier to get a DP mobo with 8 slots (I have one and am planning to swap my DP's for it, if it ends up never popping out of its full power fan mode even after a repaste - even though it otherwise works fine - my ears can't bear it anymore!)
 
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This is probably possible, however some extra resistors would likely need to be soldered too - look for empty resistor pads around the DIMM slot pads
I bought two G5 june 2004 1.8's a couple days ago, so far they are in transit and I'm just pondering possible modifications
 
This is probably possible
I doubt it. There's probably a good reason why the slots aren't populated, and if my experience with server and workstation hardware is to be believed, it's because the unpopulated slots are tied to the also unpopulated second processor. Even if you were to populate all the board components to add the slots, odds are the slots won't be recognised due to there being no processor to see them.

You can likely see this in action by populating a DP logic board with only one processor and seeing how much RAM gets detected.
 
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