Had to take the testing a step further and see if I could "calibrate" the 2.5ghz CPUs to the board... Here is the results:

Calibration Results for 2.5ghz CPU Swap

**My 2.7ghz board would never calibrate correctly and kept throwing a "CPU intake fan speed error". I also heard horror stories of ASD Tool actually bricking the logic board, so again, do it at yer own risk! :)**

ok, what about a 2.3->2.5 upgrade?

I don't see why not :) This 2.0 tower was probably released the same time around as the 2.3ghz. The thing is, there was newer released boot rom boards released/being manufactured at the time. There is a 50/50 shot your's might be one with a newer boot rom. Can you obtain an OS X install cd? All you need is just to boot the CD and go into System Profiler to see what boot rom you have. :)

Doesn't showconfig show the rom version?

@bash64

I believe not. I just dug up these instructions. Might be worth a shot:

1. Shut down.
2. Start up and hold down cmd-opt-o-f
3. The Boot ROM Revision is displayed at the top of the screen.
4. Type "bye" followed by <return> to continue starting up in Mac OS.

Let us know. :)

Going home in 30 minutes.
Will post my rom then.

Will also be installing a 256gb ssd tonight.
Gonna be killer speed.

I have rom 5.2.4.f1 on my mac g5 2.3ghz


I just replaced the main hard drive with a 256gb ssd.
It is now unbelievably fast.

However, for some strange reason I have seen no improvement with the running of Windows XP using the b.o.c.h.s. emulator.
Back to tweaking...

@Doffo: You done much more that an entire mac world did not in g5 cpu upgrade. Many many mac site just replies cpu swapping don't possible. My feelings was just nobody bother to try it, because the cost, because lack of knowledge.
Congrat again.

@Derringer
thanks. i appreciate the kind input.

@bash64
That is GOOD news. thats the boot rom my current 2.7 g5 has... :) its risking it but imma bet a 2.7 cpu set will boot up. thing is most setups are leaking so convert it to heatsinks and calibrate using the Apple service diagnostics CD. get the one that supports G5

I have already bought all the fans, molex connectors, and heat sinks.
I think you provided the ebay links to do so.
I only see one 2.7 set on ebay:

http://www.ebay.com/itm/Apple-G5-CPU-PROSESSOR-DUO-2-7-GHZ-with-Liquid-Cooling-Heatsink-603-6220-A-/121106601274?pt=CPUs&hash=item1c3284153a

@doffo,

What is the part number on your 2.7ghz cpus?
I don't want to buy the wrong thing.
Thanks

Also, is there anyway you can message me the name of a torrent that will download the apple cd to resync the cpus?

Will a cpu set from an xserve or a HP server work?


[ Edited by bash64 05.08.2013 - 17:52 ]

> Will a cpu set from an xserve or a HP server work?

There were HP servers with PPC970?

I dont know if an HP ever had those.. :P

Also, I don't think there were 2.7ghz xserve g5 cpus, but I did successfully swap some xserve 2.3ghz and they did just fine. :)

> I don't think there were 2.7ghz xserve g5 cpus

True, 2.3 Ghz was maximum.

http://en.wikipedia.org/wiki/Xserve#Xserve_G5

Does anyone have a set of 2.5 cpus they can sell me?
Buying from ebay is somewhat risky.
Better yet, do you have a set of 2.7 cpus?
thanks

I found a torrent with all 25gb worth of Apple Service Diagnostic CDs.
I had to use a shell command called dmg2img.exe to convert the file into an iso:
>dmg2igm.exe {source}.dmg {dest}.iso

Burned the 2.5.8 cd and I passed all the tests.
It ran my fans so hard the g5 sounded like a jet engine.

I seen a few sets of 2.5ghz on ebay for a decent price...

$38ish after shipping. Least the auction says they work.

2.5ghz g5 CPU set on ebay

I was able to swap 2.7ghz Processors into a board that had 2.3. I bought both machines, but the LCS from the 2.7 machine had leaked and destroyed the PSU in that unit. After I clean the processor boards and mounted the heatsinks from the 2.3 I was able to get it to boot. Only issue is with ASD 2.5.8 the system would power off after about 5 min of thermal calibration. So I swapped motherboards but now I get the dreaded intake fan speed error during calibration.

Trying to build the optimal MorphOS/Classic Mac PPC game machine. Managed to nab a 2.5ghz set of processors with one of the better LCS modules on it so I'll see what I can do with that. There is a recycler in town that has these PCI-X 7,3 G5's on sale for $30 CDN or so if you watch it enough so I've got a few machines. I have my old Quad G5 machine that needs the LCS rebuilt but since it's not MorphOS supported I've pushed that project back. I'm gonna try a few things with the thermal calibration and report back. Might just end up sticking the 2.3's back in it since the gains would be marginal really to 2.7GHz. I bought both the 2.7 and 2.3 machine for around $30 so it's just fun to tinker, I also have a Dual 1.8 machine I have to pick up this week that I bought for $24. I figure it'll be good for spare parts.

Quote:

Yeah, my quad could use an LCS rebuild too. And its not that different than the earlier 2.5 and 2.7 GHz AGP system's coolers.
But I'd really like to figure out how to air cool the quad.

Man, talk about a blast from the past. :P Well, only about 4 years ago, but it was fun.

Depending on which firmware is on the G5 macs, you can upgrade to the 2.7GHz, but that is not always the case. I don't have the firmware versions of the G5 which would allow for a 2.7GHz upgrade.

It is ideal to also replace the fans. The stock ones will run too slow and usually doesn't help the cause. Better to have them running all the time so all the heat leaves out of the case. On stock fans, the heatsinks from my 2.0GHz got hot after a bit.

Resurrecting an old thread, I have two 2.5 GHz dual core cpus from a quad G5. Do you guys think one of these could be installed in a 2.0 or 2.3 unit?
And I'd like to ditch LCS and simply use the air coolers.
Remember, these are late 2005 models I am talking about.

Jim

[ Edited by Jim 18.05.2019 - 19:29 ]