iMac G3 (Rev A -> C) G4 CPU Upgrade

[FacnyFreddy]

I just got my board back from a fleabay service provider who reballed/reflowed a freescale G4 500MHz cpu onto my spare 400MHz Pismo board.

Delicious... and cache is working fine. He did a solid job and the price was SUPER reasonable. ($55 + S&H US)

Onto my spare 500MHz board and to see if that works like I hope. Then I get to set upto reballing a salvaged 533MHz CPU and cache.

 

 

[LightBulbFun]

very cool! glad to see its working for you im about to attempt fitting a 7410 to my Slot loading iMac G3 so ill report back on that when i finish it

 

[max1zzz]

Very nice guys

Maybe my initial problem with the iMac was a bad solder joint then

I'm thinking of trying this with my kanga (if I can get it to boot correctly), as far as I can find it has a regular 750 - but I can't find any high res logicboard shots to confirm.

 

[LightBulbFun]

thanks just got semi finished with the iMac sadly it does not boot (CRT energisers and i get a pop from the speakers but thats it) so iv just tried reflowing the G4 chip one more time to see if that will work (currently waiting for the board to cool down again) Just wondering if i cannot get this iMac to POST how up are you for doing it for me? as this is a Machine i very much want working (its my Flower Power iMac) im fully willing to pay for your services in some form (ill provide the G4 ill even give you 2 G4s and plus the One on the iMac if you want) I just really want this board/iMac to work LOL. in regards to the Kanga from my kanga although i have not taken it apart the G3s PVR tells me its a regular 750 and an early one too 2.1 Rev  vs 2.2 that was in my Beige G3 so its most likely going to be a 2.6v 750 so you will have to find a way to lower the Core voltage before fitting a G4 hope this helps

 

[LightBulbFun]

Just tried the board again and sadly it does the same thing at least its repetitive (ie it does it every time) and nothing has gone up in smoke as far as i can see so i have not shorted any main power rail to a sensitive data line for example... i think LOL I do see 2 bridged balls on the outer rim of the G4 but i dont have any way of clearing that without lifting the chip and doing it all over again using up another G4... so id like to see if Max is up for trying first

 

[max1zzz]

I'm happy to give i a go if you ship the board to me, I can lift up the chip and try reballing it but I may ultimately have to replace it as i'm not the best at reballing (but I did successfully reball a 7410 yesterday)

A couple of G4's sounds like a reasonable price (damn things have got harder to get hold of in the past couple of months)

Just need to check if your board will work in my iMac G3 (it's a first gen slotloader)

 

[LightBulbFun]

Oh awesome tho its a FP iMac its the Non US model so uses a regular 360 BGA 750 and backside L2 cache it has the model identifier of PowerMac2,2 (the first gen slot loader is 2,1 but the Lobos are swappable I also Just talked to a guy who has been an AASP guy for many years and has worked on many macs and he says there compatible too) so yeah if you could DM me your shipping addy and ill get the board and 2 7410s sent to you asap (ill also DM you my addy once i have yours) PS do you want me to cover return shipping or are you ok with covering that? (Im going to cover the shipping cost of shipping it to you of corse) how does that all sound to you

 

[FacnyFreddy]

Regarding cache speeds, is there something in either the Pismo board or the Pismo firmware that would clock down the cache on a 400MHz board vs a 500Mhz?

It was my understanding that by setting the jumpers/resistors to 500MHz would increase the clock multiplier for the cache as well as for  the CPU. Is this not the case?

 

[LightBulbFun]

AFAIK cache is tied to the CPU speed (CPU speed goes up so does cache). how far the cache can go im not sure on one hand most of the reports I have seen say L2 cache G3/G4s dont over clock that well on the other hand we do have the G4 Upgraded iBooks rocking G4s at 533Mhz with L2 cache near 300Mhz  But I dont know if L2 cache is properly enabled on those i did ask for details from the guy with the 533Mhz one (as his showed a Gauge pro reporting L2 cache) but he never responded.

 

[FacnyFreddy]

AFAIK cache is tied to the CPU speed (CPU speed goes up so does cache). how far the cache can go im not sure on one hand most of the reports I have seen say L2 cache G3/G4s dont over clock that well on the other hand we do have the G4 Upgraded iBooks rocking G4s at 533Mhz with L2 cache near 300Mhz  But I dont know if L2 cache is properly enabled on those i did ask for details from the guy with the 533Mhz one (as his showed a Gauge pro reporting L2 cache) but he never responded.

This is why I am leaning towards harvesting the cache from a 533MHz G4 Powermac board along with the CPU. The thermals are also inline with the other research I have done. And the voltages are just fine.

I thought there was something in the firmware or such that would detect cache misses/errors and then drop it down a setting at the OS.

 

[LightBulbFun]

another status update still mucking around with the Pismo

I got the thing clocked up to 600Mhz! its quite fast at that speed especially with the 1MB L2, I did get it benchmarked in tiger. tho while doing so in Leopard the L2 cache died again mid benchmark and crashed OS X LOL and when i rebooted it had same symptoms as before so prolly a dodgy ball again, so ill give the CPU another reflow tommrow kinda glad it was the L2 and not the CPU it self as the L2 is a known issue not related to clock speed (the fan had not even kicked on at the point it panicked). this is still with the original stock L2 cache chips as it was back when it was a 400Mhz G3 board I have not replaced those or anything.

BTW I noticed on both the Pismo and my iMac with gauge pro in OS9 it will report the bus/cpu frequency a bit higher then normal for the first couple minutes of running then it will settle to steady normal 99.9Mhz Bus speed in the case of the Pismo and iMac im not sure if this is a bug in the app or really is the bus speed being a bit lose for whatever reason.

https://browser.geekbench.com/geekbench2/2625681

 

[TarableCode]

This makes me moist.

Are there similar upgrade paths for the iBook SE?

 

[LightBulbFun]

LOL!

the FireWire clamshells (I assume thats what your referring to) use the 750CXe CPUs and are not compatible with any sort of G4 upgrade the only iBook G3 that is compatible is the first non FW Clamshell iBooks (PowerBook2,1)

 

[belgaonkar]

Check out "CPU director" for an accurate clock speed gauge on OS X. Keep in mind, it won't work after 10.4.9, so I have just left the system running at 10.4.0 and it works like a dream.

 

[TarableCode]

LOL!

the FireWire clamshells (I assume thats what your referring to) use the 750CXe CPUs and are not compatible with any sort of G4 upgrade the only iBook G3 that is compatible is the first non FW Clamshell iBooks (PowerBook2,1)

Bah!

I might pick up a CPU anyway before the supply dries up, and maybe in the future a Powerbook will catch my eye.

Good stuff though, pretty amazing to see all the progress.

 

[LightBulbFun]

@belgaonkar I do recommend updating to 10.4.11 once your done with said app as the update contains many bug fixes and improvements btw got any pictures of it running OS X? system profiler shots etc? I have been asking for a good while now

@TarableCode theres still a few for sale but yeah thats not a bad idea i have noticed that since this hole thing got off the ground a lot more 7410s are selling (luckily the seller i got mine from has not bumped the price up silly. a bunch of other sellers have even before this thing started)

 

[LightBulbFun]

Gave it another reflow. the L2 cache still not showing up/is reporting cache failure in POST messages. I dont want to keep reflowing the board as it is getting kinda crispy so to speak so ill just leave as is a 600Mhz G4 Pismo with no L2 cache LOL tho maybe if i can learn how to reball i might lift the chip reball it clean up the pads again and give it another go as I highly suspect its a dodgy ball under the CPU and not the L2 chips. but apart from that the thing is still nice and stable at 600Mhz

 

[belgaonkar]

@lightbulb- here you go! I still have struggled to install 10.5 on it, but it's running tiger!



All versions of Mac OS (9 &10) see the CPU as a 100MHZ G4, although Gauge Pro and CPU Director show the correct clock speed.





Has anyone had success running GeekBench? Every time I try to run it, the system freezes and requires a reboot. Thermals are a serious problem on these clamshells. 

 

[LightBulbFun]

very coo thanks heh I did warn you about the thermals is there any way to adapt a bigger heatsink perhaps out of copper? also what sort of issues have you been having with Leopard and where/what part does geekbench/the system freeze on?

also I do appreciate the shots but I did speficly ask for system profiler shots as that tells me some things about what OpenFirmware on the clamshell thinks about the 7410 and if your firmware is fully up to date.

 

[belgaonkar]

The iBook has no clue what to do with the CPU.



damn thing is always rotating the pictures.