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caesar148

macrumors newbie
Original poster
Aug 10, 2012
3
0
Hi all,

I'm new to the Mac world. Been a Windows user all my life - till now. Well I chanced upon a 1.8GHz DP G5 computer in my company's trash bin and I also had access to a 2.0GHz DP G5 with a dead mother board. The 1.8GHz computer ran fine but was kind of slow so I decided to upgrade the processor to the 2.0GHz version. After much digging around on the internet on how to remove and install the processor, I decided to do some brain surgery. Surprisingly it worked. Now I'm wondering whether I can up the speed with a 2.3GHz or even a 2.7GHz processor. Any advice if this is possible?

The original computer is a Nov 2003 model, model number M9393LL/A A1047, PowerMac7,2.
 
Unlikely. G5 processors don't like being switched between models. It's very possible that the FBUS speed in your current machine is well below what it should be because it's in a safe mode due to the unrecognized processors.
 
Unlikely. G5 processors don't like being switched between models. It's very possible that the FBUS speed in your current machine is well below what it should be because it's in a safe mode due to the unrecognized processors.

How do I tell if it is running in safe mode?
 
Click on the Apple logo in the top left, select About This Mac. Click on More Info... In the hardware section of the overview, look for Bus Speed. What speed it is reporting?
 
G5 processor

Unlikely the computer worked with the new processor, if it did it was defaulted to the original speed which is 2X the motherboard bus speed. The 1.8 was 900 MHz, 2.0 was 1000 MHz and so on. The systems should not function at any other speed. My dual won't even boot without the correct model 2.0 ghz processor line.

Good luck, also ASD 2.5.8 is required to reset full fan speed when changing processors and other hardware that monitors heat in the system including the motherboard.
 
Yes, you are right. The fan is roaring like a 747. From what I understand I need to do a thermal calibration. Let me see if I can find a site to download ASD 2.5.8.
 
Unlikely. G5 processors don't like being switched between models. It's very possible that the FBUS speed in your current machine is well below what it should be because it's in a safe mode due to the unrecognized processors.

Unrecognized CPU in G5 upper slot = no boot.
OP is kinda lucky - only some boards will accept higher clocked CPUs. I only know about this kind of swaps - 1.8 to 2.0, 1.6 to 1.8 (1.6->1.8 I've done personally). I've tried 2.3 and 2.5 on few 2.0 and 1.8 boards without success.
OP: If it booted and working - thermal calibration and you'll be good to go (if it would pass ofc).
 
Down clock

Doesnt it default the chip to 2x the board bus speed no matter what the chip is at? I was sure that was the default.


If you need a copy of the ASD send me an email and I'll send you a copy, I'm sure I have one around.
 
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