How do you identify Dual-CPU PowerMac G4's from Single-CPU models?

LOLZpersonok

macrumors 6502a
Original poster
Aug 10, 2012
711
14
Calgary, Canada
I want to get one as a secondary computer, but I want to be sure mine can accommodate and utilize two physical CPU's for added performance.

How do I tell if it has Dual-CPU capabilities, and if it does, what is the most powerful CPU's I can install in each socket? I'd need to know what brand and where I can purchase them too.
 

LeoTheLion89

macrumors 6502
Feb 14, 2012
353
0
I want to get one as a secondary computer, but I want to be sure mine can accommodate and utilize two physical CPU's for added performance.

How do I tell if it has Dual-CPU capabilities, and if it does, what is the most powerful CPU's I can install in each socket? I'd need to know what brand and where I can purchase them too.
the most powerful G4s are indeed the Mirror Drive Doors (MDD) G4s that last models came with Dual 1.42GHz (i think dual someone correct me if wrong) that is a total of 2.84GHz of processing power all MDD models support Dual CPUs so it dont make much of a difference if u buy it with a Single or Dual CPU as u can upgrade them later however i cant find any above 1.25GHz. The Brand would be from Apple best place to look is eBay theres a few on sale (Processors) now also plenly of MDD Macs as well.
 

Intell

macrumors P6
Jan 24, 2010
18,883
372
Inside
Any G4 that is a Gigabit Ethernet or newer model can support a dual core G4. This includes the G4 Cube. Some Sawtooth models can support dual core G4's, but you'll have to run a program on them to check their board revision first. Nothing older than a Sawtooth can support dual G4's.

The fastest G4 upgrade would be the dual 1.8Ghz 7448 G4. I think both Sonnet and PowerLogix made one. But they are very rare and go for about $600, used.
 

Nameci

macrumors 68000
Oct 29, 2010
1,944
8
The Philippines...

LeoTheLion89

macrumors 6502
Feb 14, 2012
353
0
Any G4 that is a Gigabit Ethernet or newer model can support a dual core G4. This includes the G4 Cube. Some Sawtooth models can support dual core G4's, but you'll have to run a program on them to check their board revision first. Nothing older than a Sawtooth can support dual G4's.

The fastest G4 upgrade would be the dual 1.8Ghz 7448 G4. I think both Sonnet and PowerLogix made one. But they are very rare and go for about $600, used.
the Cube huh? ive never seen a CPU upgrade for a cube nor ever heard of one although i never cared to look into it either.
 

Intell

macrumors P6
Jan 24, 2010
18,883
372
Inside
the Cube huh? ive never seen a CPU upgrade for a cube nor ever heard of one although i never cared to look into it either.
Yep. They upgrade well. I've got a 1.5Ghz in mine and it's made a big difference over the 450Mhz stock G4. Electronically, Cube's are just like Gigabit Ethernet PowerMacs.
 

LOLZpersonok

macrumors 6502a
Original poster
Aug 10, 2012
711
14
Calgary, Canada
the most powerful G4s are indeed the Mirror Drive Doors (MDD) G4s that last models came with Dual 1.42GHz (i think dual someone correct me if wrong) that is a total of 2.84GHz of processing power all MDD models support Dual CPUs so it dont make much of a difference if u buy it with a Single or Dual CPU as u can upgrade them later however i cant find any above 1.25GHz. The Brand would be from Apple best place to look is eBay theres a few on sale (Processors) now also plenly of MDD Macs as well.
Cool, Thanks for the response. If you hadn't responded with this information, I'd probably skip out on the $65 one I found, which I now realize is a MDD model. I'd better buy it quick!
 

Daedalus256

macrumors 6502
Nov 7, 2005
308
0
Pittsburgh, PA
the most powerful G4s are indeed the Mirror Drive Doors (MDD) G4s that last models came with Dual 1.42GHz (i think dual someone correct me if wrong) that is a total of 2.84GHz of processing power all MDD models support Dual CPUs so it dont make much of a difference if u buy it with a Single or Dual CPU as u can upgrade them later however i cant find any above 1.25GHz. The Brand would be from Apple best place to look is eBay theres a few on sale (Processors) now also plenly of MDD Macs as well.
No. That is not how it works. The dual processors are not like dual-core machines. I have a DP 800Mhz QS and it certainly doesn't run at "1.6Ghz". Only really applications that utilize any sort of dual-processor programming are able to access both. They don't work in tandem.
 

SuperJudge

macrumors 6502
Apr 2, 2008
449
4
The Triangle, NC
No. That is not how it works. The dual processors are not like dual-core machines. I have a DP 800Mhz QS and it certainly doesn't run at "1.6Ghz". Only really applications that utilize any sort of dual-processor programming are able to access both. They don't work in tandem.
Precisely.

Now, in a multithreaded OS, like Mac OS X, you do see performance gains from dual processors, but as a rule it's more like 70-75% of the combined clockspeed. Of course, that doesn't apply to single threaded apps, only to overall performance.
 

Bug-Creator

macrumors 6502a
May 30, 2011
583
2,274
Germany
The fastest G4 upgrade would be the dual 1.8Ghz 7448 G4. I think both Sonnet and PowerLogix made one. But they are very rare and go for about $600, used.
At that price I'd rather look out for a used QuickSilver (or older) with such a card allready installed.

Got mine (with 2x1.8GHz Sonnet) for 150Euro and the same guy also had one with a 1x1.8GHz on sale (funny that auction ended 15Euro higher). At the same time there was a 1.8GHz Cube wich ended at somewhere around 190Euro.

One should also remember that in everyday use 1x1.8GHz might actually be faster than 2x1GHz.