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Fastest, RELIABLE used Mac G5 Quad?

I have a need for the fastest PPC (non-Intel) machine in order to run certain software under Tiger for the rest of my life (I have a short personal life expectancy, under 18 months or so). I'd need it to be noticeably faster than my current machine, of course.

There are some G5-Quad and G5-Dual machines available on eBay. I understand that some G5 Quad models are better avoided due to power supply problems, but I'm not sure which ones.

I'd be grateful for any input from the experienced forum contributors who may have any advice.

Thanks in advance.

Dual 1.25MHz MDD G4, 2GB RAM, 4 int dr.3ext FW drives, Mac OS X (10.4.11), nVidia 7800 GS 425MHz 256MB video card, dual 22" CRT monitors

Posted on Aug 2, 2011 4:09 AM

Best reply

japamac

Level 7

24,400 points

Posted on Aug 2, 2011 5:52 AM

Hi-

The Quad is the fastest PPC machine.

They didn't have any more power supply issues than other models, and are possibly one of the more reliable machines.

http://www.macintouch.com/reliability/pmg5.html

The one caution point for the Quad is the liquid cooling.

However, I haven't seen that the Quad is a prone to failure as early LCS machines (all 2.5 GHz and 2.7 GHz dual processor G5's).

If one wanted to forego the potential minefield of the LCS, a late 2005 2.3 GHz dual core would be the fastest air cooled machine.

Geekbench CPU and Memory Benchmark:

Power Mac G5 (Late 2005)
PowerPC G5 (970MP) 2.5 GHz (4 cores)

3318

Power Mac G5 (June 2004)
PowerPC G5 (970FX) 2.7 GHz (2 cores)

2259

Power Mac G5 (June 2004)
PowerPC G5 (970FX) 2.5 GHz (2 cores)

2100

Power Mac G5 (Late 2005)
PowerPC G5 (970MP) 2.3 GHz (2 cores)

2084

View in context

65 replies

BDAqua

Level 10

239,483 points

Sep 1, 2011 1:39 PM in response to Ramón G Castañeda

Excellent link, thanks! 🙂

Sep 2, 2011 2:15 AM in response to BDAqua

BDAqua wrote:

Try iStat Menus…

It turns out that Hardware Monitor also clarifies whether your Quad has the newer single pump or not:

"Why do some PowerMac G5 systems with 4 CPU cores sometimes not display values for their second cooling pump?

"Apple distributes two different versions of the "quad" PowerMac G5 computers: Some of them are equipped with two pumps for the liquid cooling system, while others contain a revised version of the cooling system with only one pump. Hardware Monitor correctly reflects the situation for each version. If the sensor for the second pump is missing (label "CPU B Radiator Pump"), your computer uses a liquid cooling system with one pump only".

http://www.bresink.com/osx/216202/issues.html

According to this utility, my Quad has the single pump.

Trying to clarify this with the tech who reassembled the Quad in a replacement enclosure, he informs me that I had "misunderstood" him on Wednesday. His veracity is now somewhat in question because of unrelated issues, so I'll just forget what he told me or—to put it kindly—what I understood him to be telling me about the pump.

As I explained before, it's a moot point anyway. Whatever kind of pump it has I'm stuck with. I'll just keep my fingers crossed and will continue to monitor the sensors for any sign of trouble.

romko23

Level 2

408 points

Sep 2, 2011 11:01 PM in response to Ramón G Castañeda

Do please show us a picture of the single pump?? I know mine is single since I saw it with my own eyes.. Give me an idea of what it looks like..

Thanks a lot!

Roman

romko23

Level 2

408 points

Sep 2, 2011 11:17 PM in response to BDAqua

I really think you need to check what LCS you have.. If Ramon says what is correct, the dual pump is a walking time bomb just ready to go off.. You might want to convert over to the single pump as its more reliable. So far, we have yet to see an ACTUAL picture of the single pump..

Sep 2, 2011 11:34 PM in response to romko23

romko23 wrote:

Do please show us a picture of the single pump??

Well, I won't be able to take an image of the pump for a while—until I learn how to remove the protective aluminum cover. At this point, I'm busy cloning the boot drive on my MDD G4 to the G5 Quad boot drive. It has been going for about two hours and my estimate is that it will take at least another six or seven hours to complete. After that, I'll look into opening the G5 Quad Service Manual, which I have in PDF format, to refresh my memory. If my recollection is correct, removing the cover over the radiator unit involves using an Exacto knife to pop some rivets, and if that's the case, I'd be very reluctant to undertake the task myself. I'll let you know one way or the other in a few days.

Thanks for your continued interest.

romko23

Level 2

408 points

Sep 2, 2011 11:56 PM in response to Ramón G Castañeda

Given I too have the same service guide, there is a picture of what looks like the only TWO versions in the Quads. The picture on the left is the single pump, while the picture on the right is the DUAL pump. Unless there was a third "mystery" LCS that never made it into the service guide, I am certain that the pump on the left is the single one.

Again, I don't know for sure.. Yes, all you do is take an xacto knife or other sharp thingy and remove the rivet. You can re-use the rivet, just be careful not to break it. In fact really, you don't even need the rivet. Then the G5 panel comes off from lifting it either from the bottom or top.

Sep 3, 2011 12:10 AM in response to romko23

So, I wouldn't want to go through the process before securing the extra rivets in case on or more get damaged or lost.

romko23

Level 2

408 points

Sep 3, 2011 12:22 AM in response to Ramón G Castañeda

You really don't need the rivet. I don't use it anymore on my G5 since I know the G5 panel is held together by snaps. Its still very secure even without the rivet. And as I said, I have been using the same rivet for awhile now.. so long as you are careful in pulling it out, it won't break and you can re-use it if you want. Dont take literally what Apple says.. use your best thinking on it. Once you see how the G5 Panel is locked in place, you will not need the rivet since the clamps for the cover are pretty sturdy.

Sep 3, 2011 12:47 AM in response to romko23

romko23 wrote:

You really don't need the rivet…

Well, the service manual says otherwise, and I have no reason to doubt its veracity. Sorry.

romko23

Level 2

408 points

Sep 3, 2011 9:59 AM in response to Ramón G Castañeda

Actually my AASR(apple service and repair rep) told me personally I didn't need it, so I don't take literally whats written in the service guide in terms of the rivet.. just like I don't have the rivet to hold the airport runnoff card.

Sep 3, 2011 1:51 PM in response to romko23

Romko,

I fully understand and respect your freedom to take a stand on this. I hope you respect my position too.

romko23

Level 2

408 points

Sep 3, 2011 7:23 PM in response to Ramón G Castañeda

I respect it also.. just want to see what the single pump looks like, because mine reports also CPU A and CPU B as well, but the person whom I got the G5 from told me it IS the single pump model, also known as Panassonic and not the dual.

BDAqua

Level 10

239,483 points

Sep 3, 2011 10:09 PM in response to romko23

mine reports also CPU A and CPU B as well

It reports Pump RPMs for both???

romko23

Level 2

408 points

Sep 3, 2011 11:53 PM in response to BDAqua

Who knows.. all I know is that I now have the single pump LCS, but just to be sure I want to see a picture of it.. Yes, even mine reports CPU A AND B.. I am not sure where Ramon is getting his info from, but I called a friend tonite and he told me the single pump reports the same way as the dual.. here are my temps to show you..

CPU A Core 1 Diode: 106.1 F

CPU A Core 2 Diode 104.6 F

CPU B Core 1 Diode 107.9 F

CPU B Core 2 Diode 117.1 F

Now this is the single pump version.. I called the person whom sold this Quad to me for 300.00 - the good news is it was an Apple Repair Tech and he told me that it is quite normal for one of the cores to score 5-10 degrees higher than the rest. He told me in a nutshell my Quad with dual pumps was a goner.

Sep 4, 2011 12:30 AM in response to romko23

romko23 wrote:

…but I called a friend tonite and he told me the single pump reports the same way as the dual..

Romko,

You have to stop listening to idiots. Really.

If you have the Hardware Monitor application installed, it will report a SINGLE pump if you have only one, and it will report TWO if you have a dual.

Fastest, RELIABLE used Mac G5 Quad?