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Leopard on G3 and other question

Arkious

Arkious

macrumors 6502a
Original poster
Mar 14, 2011
583
0
Newcastle, UK
Hi guys, I know that by apples terms Leopard can't run on G3s but I have seen many pictures and videos etc that if you install leopard via another computer then transplant the hard drive you can get it to run?

Was just wondering anyways.

Also does anyone know of a way to overclock the later 600MHz+ iMac G3s? I have done the older slots and trays but the layout of
The newer SE and DV iMacs are different

Thanks ^.^
 
You can get leopard running on any G4 very easily. I once had it running on a stock 500mhz sawtooth (1GB RAM). You can not run it on a G3. The G3s wouldn't be able to handle it even if you could.
 
rjcalifornia said:
No, you cannot overclock your G3.
Click to expand...

Wrong. I've overclocked both my G3 iMacs. 600@700 (Snow) and 450@500 (DV).

Arkious, get 750CXE datasheet and you'll find PLL settings there. Unfortunately I didn't take pictures of resistors location when doing mine, but it's easy to figure out. That same for voltage regulator. 600 won't go higher than 700 MHz, because it's max factory speed for 750CXE.
 
If you've got a G3 with a socketed CPU you can drop in a compatible G4 processor and run Leopard that way with some work (the older machine the more work is needed to add back the missing hardware drivers) - I have it running on a beige G3 tower this way. You generally have to do the install on another machine as without kexts from Tiger and Leopard betas that contain the missing drivers, it will fail to boot with the "unable to find driver for this platform" error, so you can't easily boot from the DVD.

Otherwise it won't work due to Leopard having been compiled by Apple for PPC AltiVec and Intel only.
 
Sorry

But Leopard would run horrible on a G3.. Even if it were to run up to 10.5.2, it was not designed for the G3. While I consider and support all PowerPC processors, G3 included, I cannot approve of Leopard being a choice for a G3.. Even a G3 900 or GE 1GHZ(IBM) would struggle with it.

Leopard is too much dependent on core image graphics at the hardware and software level.

It requires a G4 or G5.. We know it runs on Intel though.
 
Brilliant thanks very much for your replies guys, ive just been tinkering on with it (cleaned all plastics etc) and its quite a nice computer for what it is, ive never really played with the slot loaders before... only the one i turned into the iMacquarium ^.^

I have no intention of trying somthing with this one, i just wanted to get the most out of it for general use. The hard drive sounds terrible so ive ordered an 80GB 2.5" WD Scorpio Black SATA drive with an IDE adapter. My hopes being that the smaller drives are quieter than their desktop counterparts. Ive also ordered 1GB of low density sdram, its currently running 512mb which aint bad but cant go wrong with maxing it. I have a little USB wireless adapter that id like to get working but i think it needs 10.4+ and im only at 10.3 atm as i dont have a dvd drive to install it. (future upgrade when i find out where to get a suitable drive).

but as for 10.5, was just wondering really, bit of a mess on :) but 10.4 was great with a leopard skin pack so i will do that again.

666sheep said:
Wrong. I've overclocked both my G3 iMacs. 600@700 (Snow) and 450@500 (DV).

Arkious, get 750CXE datasheet and you'll find PLL settings there. Unfortunately I didn't take pictures of resistors location when doing mine, but it's easy to figure out. That same for voltage regulator. 600 won't go higher than 700 MHz, because it's max factory speed for 750CXE.
Click to expand...

Brilliant thanks very much for that mate, i understand that the 450 and 500s arent much different to the tray loader overclocks when i did that. i just couldnt find the PLL resistors. i didnt know however that you could alter the voltage regulator, it would be good to get that 100MHz boost either way! I will let you know if i find the stuff i need.

----------
666sheep said:
Wrong. I've overclocked both my G3 iMacs. 600@700 (Snow) and 450@500 (DV).

Arkious, get 750CXE datasheet and you'll find PLL settings there. Unfortunately I didn't take pictures of resistors location when doing mine, but it's easy to figure out. That same for voltage regulator. 600 won't go higher than 700 MHz, because it's max factory speed for 750CXE.
Click to expand...

ABCEBD38-1754-4A3D-A963-0A327EB2E6BF-18781-00000830E50B1ADA_zpsc61b391b.jpg


do they look familiar? R159 - R168?

also

https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/04D8DD112C160E0887256A0900615D50/$file/7xxp_ds_32.pdf

page 40 gives the PLL settings

looking at it the board and table, it looks like 0100 is 2x bus frequency

does that mean i switch it to 1000 so that its 3x?
 
Last edited:
Arkious said:
do they look familiar? R159 - R168?

also

https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/04D8DD112C160E0887256A0900615D50/$file/7xxp_ds_32.pdf

page 40 gives the PLL settings

looking at it the board and table, it looks like 0100 is 2x bus frequency

does that mean i switch it to 1000 so that its 3x?
Click to expand...

Yep, these are the right ones.

I've used this datasheet: https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/31777DF6FD56656387256B1B0076E671
but table is that same.
To achieve 700 MHz you need to move ones on the right to the left and vice versa.

I'm not sure about bus multiplier ATM, I didn't touch it IIRC.
I could check in mine (but not until monday/tuesday) if I needed to bump voltage - it was some time ago, so I don't remember now.
 
666sheep said:
Yep, these are the right ones.

I've used this datasheet: https://www-01.ibm.com/chips/techlib/techlib.nsf/techdocs/31777DF6FD56656387256B1B0076E671
but table is that same.
To achieve 700 MHz you need to move ones on the right to the left and vice versa.

I'm not sure about bus multiplier ATM, I didn't touch it IIRC.
I could check in mine (but not until monday/tuesday) if I needed to bump voltage - it was some time ago, so I don't remember now.
Click to expand...

Well thankyou very much for your feedback, i will have a go switching them tomrrow and see what happens, i will report back
 
i have done exactly that, switched them round and it fails to start

no boot tone no nothing

i understand that its a 100MHz frequency x the 6 multiplier of 1101 = 600MHz

and that we are trying to achieve a x 7 multiplier of 0010 = 700MHz

i guess we need power? i don't have a clue how to do that though
 
Last edited:
i realised what i did wrong,

i had knocked a joint off the board when soldering :-(

NEVER FAIL! ARKIOUS IS HERE! lol xD!!!

79511547-C4A7-4BCD-AF31-04A069B6F5DE-1014-00000085E2055A59_zps8920827f.jpg


i tracked it back to the CPU and attached a bit of wire over to the CPU and it worked :)

348745F2-24F0-47E7-B7F9-5302E9904356-1014-00000085E7BF6C51_zps5d9df607.jpg


thanks a bunch buddy. i was tempted on trying the 7.5x multiplier for a 750MHz but im happy with 100MHz extra

approx 16.5% faster ^.^
 
hmmm... not good

i put the thing back together and now it fails to start again

think it might be a voltage issue?

when you press the power button everything goes to start but fails to boot. all the pins are fine when tested with a multimeter

any idea?
 
ok, those resistors must be used. when i put the wire across i did not use the resistor, i added the resistor to the fix and it starts no problem after testing 5 times powering up and down.
 
666sheep said:
Congrats. I've missed your thread update somehow.
I've tried 750 and 800 MHz with different voltages - no go.
Later I've found that 700 was maximum possible:
http://www.myetymology.com/encyclopedia/PowerPC_G3.html
This was also described in one of datasheets but I can't find in which now.

BTW, I didn't use resistors, just made bridges from solder on needed locations.
Click to expand...

Ahh okay, i didnt try it as im quite happy getting the extra 100 :)

Strange that yours worked, mine simply wouldnt start, so i had to put the resistor back in with it. but i dont mind, it works :)
 
i guess if you have another mac you could clone or install leapord via firewire by
pressing f or maybe changing the logic board?
 
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