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

[FacnyFreddy]

I got word back from my FleaBay contact who said he would be interested in testing this out with a spare Pismo board but only if we tried it with a NEW 7410 vs messing with reballing a used CPU for now.

He didn't want to touch this unless he had access to a Powerbook to test this with, and he agreed to move forward if I sent him my spare Pismo. I sent over the links to the iFixit instructions on the CPUboard installation and he is now totally onboard.

$55 for the CPU swap and another $15 for the S&H of the components back to me. He doesn't want to mess with moving resistors to change the clock rate as the cache might be affected, so I am going to test that on my end and he will (possibly) incorporate that with the process if it is successful on my end.

He will NOT extract/reball a CPU from an existing G4 board at this time. Only new CPUs until this gets tested.

So I am waiting on the CPUs from China to arrive (ordered 2 of them) and will see how it goes. We call this "aggressively waiting"

 

[FacnyFreddy]

Don't see why not.  G4 ZIF upgrades were available for G3 Beige and B&W machines back in the day.  If the parts are the same layout, you'd remove the G3 IC from the ZIF module and drop a G4 in its place.

You can "harvest" G4 processors from the G4 533MHz cpu boards from the Power Macs. There are quite a few of these on FleaBay (ebay) for like $10.

The problem is that they will need to be reballed prior to putting them onto to G3 ZIF boards. I believe the ZIF boards had an actual BGA installed into intermediate board and then installed with new cache.

Its possible, but, I don't know of anyone who has done this in recent years. I will look to see if we still have the older G3 (beige) unit in our attic and if it still has the ZIF installed. I don't know for sure.

 

[LightBulbFun]

Sounds like a plan! Pismo should work nicely with a G4 upgrade mine has been working perfectly fine temps are good as well with the stock heatsink setup a small amount of AS5.

in regards to upgrading the PPC G3 NuBus Card and the PowerStar CPU upgrade card what you have to check is specifically what G3 does it use? as noted above the 200-266Mhz ones are rated at 2.6v which is far too much for a 7410 to handle but the 300Mhz and faster G3s use a 1.9v-2v vcore which 7410s have proven to be able to handle. if it uses one of the lower voltage G3s then theres a good chance you could solder on a MPC7410 to it and have it work. I say it should work but you dont know exactly what they did so i cant 100% guarantee it 

 

[max1zzz]

Anything with a 360 pin 750 can in theory be upgraded, just the slower, higher voltage cards will need a voltage modification as well

 

[FacnyFreddy]

Well, I sent my G3 400MHz Pismo board off to be reballed. I got the 7410 from the guys in China a week or so ago. I have a 2nd CPU from them that I ordered at the same time.

Reballing service said it would take about 4-6 weeks turn around time.

If the 500MHz on the 400MHz board works well, I'll ship them one of my beloved 500MHz G3 boards and have them do it with that as well.

I've not started removing the 533MHz cpu and faster cache from a graphite mac yet. Been too busy with work, But, I have the reballing template and spheres in my bit bucket.

I'll try removing the cache and CPU once I get the turn around from the reballer.

I would really like to get a 550MHz Pismo running for some older software and get my Pismo in 100% working order. (Dug out my copy of Filemaker 8.5 the other day... its kinda slow on the G3 500Mhz)

 

[belgaonkar]

Here's the money shot! Amazing job max1zzz!

Running at 532.6MHZ and idles at a cool 60F  B)

 

[belgaonkar]

I wonder if this is just the system reporting incorrectly, but it has done it a couple of times. The first five minutes after boot up the CPU seems to run at 538MHZ and once it warms it its goes down to 532. I would call this thermal bottlenecking, but I don't think the CPU can even do that? Maybe a voltage spike after boot up? Anyone know?

 

[EvieSigma]

Impressive results! I guess I'll have to have max upgrade my G3 as well!

 

[LightBulbFun]

very nice to see the iBook running do note that the thermal diode on 750/7400/7410s are not calibrated normally so i would not really believe that thermal read out. in regards to clock speed i think its just variants in the program try comparing it to another program and see what it reports, the CPU is not adjusting any multipliers as your with in points of one and the 7410 only goes up in increments of .5. btw i see its recognising your L2 cache does OS9 system profiler report it? and is the firmware on this iBook fully up to date? just collecting some information also got OS X installed? it would be cool to see esp leo (btw how is thermals under a stress test? and once OS X is on there geekbench it )

 

[belgaonkar]

Firmware is up to date, still waiting on the RAM upgrade to come in the mail. Keep in mind this is the original non firewire model meaning it cannot even run tiger unless the ISO is modified. The machine seems to over heat when doing intensive tasks like an OS install. I am currently working on replacing the speaker with a small fan.

 

[LightBulbFun]

Cool. So your running firmware 4.1.9 then? im well aware That this is a PowerBook2,1, in that regard you dont have to modify the tiger ISO to install Tiger on it, with a couple OF commands you can temporarily fake your machine as a PowerBook2,2 and install tiger using a stock tiger CD. (well one long command actually yay for forth you confusing little...). do you have a shot of system profiler in OS 9? im want to see if it sees the L2 cache and if it reports the CPU speed correctly with the firmware fully updated. (as the speed and L2 where not reported properly with Maxs iBook and i suspect thats because he could not update his firmware for some reason) im still waiting to try a G4 upgrade on a (slot loading preferably) iMac G3 at some point. kinda surprised to see the L2 cache being able to run so fast would be fun to see if it could be upgraded to 1MB of L2 and i hope you can get the thermals under control not surprised to see it struggling with a 533Mhz 7410 LOL

 

[FacnyFreddy]

Minor update.

My contact for the reball work received the G3-400Mhz board and Freescale G4 cpu. He is a bit back logged, but, I plan to start extracting the G4-7410LE 533MHz cpu from my harvested graphite board here shortly.

I have all the tools to do the extraction and now just need to block out a day to get it done. I'm gong to try taking out the cache chips as well, since the board is going to be ditched anyhow. I might try and scavenge the resistors for the clock speed settings, as those might come in handy if I bugger the ones on the Pismo board.

Any tips on replacing the soldered cache chips?

 

[max1zzz]

Yep, drag solder them. Desolder the old ones, clean the board with desoldering braid, put the new chips on the board and run a bead of solder over all the pins then go over them with desoldering braid. This should leave you with nice neatly soldered cache chips

That said, i'm not sure the cache chips where causing the problem I got belgaonkar's board to run at 533mhz with no problem and that was originally 300mhz

 

[FacnyFreddy]

So how do I go about re-soldering the cache chips back onto the Pismo board after I clean it up? You don't "reball" them as such, but, do you "add" solder/flux to the existing cache chips and then heat them up?

 

[Bolle]

You usually leave the chips alone.

If you are using hot air to put the chips back on just tin the pads, drain everything in flux and heat up.

Or you could do it as max said and drag solder those guys back in place. For that you usually start with bare pads. Just add flux, tuck the chip down by the edge pins and then just run your nicely tinned iron along.

You would not add solder to the chip in that case either.

 

[FacnyFreddy]

I am going to wait and see how the existing 400MHz G3 -> 500MHz G4 upgrade goes and then test it out. Then onto the other Pismo board that has the 500MHz G3 with the faster cache. If  there is no difference, then I won't bother with the chips.

I am on the road to 550MHz G4 for at least one of my Pismo Powerbooks.

 

[belgaonkar]

@Lightbulbfun how did you get 10.5 on your Powerbook? The optical drive must be a CD rom drive and you must have hacked the leopard installer? Tiger is much easier to do, but I have been unsuccessful in making a leopard installer. Did you use a firewire iPod? I got to 10.4 but can't figure out how to get to 10.5

 

[belgaonkar]

As a follow up- I took it apart and cloned a copy of 10.5 on it. Lightbulb, what machine ID did you use to allow the machine to boot?

 

[LightBulbFun]

with a cloned install of 10.5 on the drive the iBook should boot right up its a uninorth machine, all the drivers (apart from video drivers) should be in Leo already, in regards to the PowerBook Pismo IIRC i booted off of a USB stick from the built in USB 1.1 ports then before it found root via UUID of the drive i quickly plugged the drive into a USB 2 CardBus card i had installed and then let it find root and it booted up and installed  (of corse i had to fake CPU Speed). the CardBus card was not directly bootable from OF. hope this helps heh

 

[LightBulbFun]

bit of a status update and some good news. so id like to report that the G4 upgraded Pismo has been working nicely since i did the CPU swap on it (never had it kernel panic for example) but the non working L2 cache was bugging me so yesterday i decided to fix it based on other reports of L2 cache failure on Pismos i decided to reflow the CPU again and a little bit of the surrounding circuits around the CPU and that seems to of done the trick its now fully reporting L2 cache and no POST failure messages here are some Pictures and geekbench results showing the improvement L2 cache makes

http://browser.primatelabs.com/geekbench2/2625052

http://browser.primatelabs.com/geekbench2/2625050