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noodle654
Jun 26, 2009, 10:45 PM
I never fully understood this topic really. I have always been interested in getting a G5, ever since they came out. I might be able to nag a Quad G5 for very cheap, but I have a question. I know that an Intel Core 2 Duo is faster than a G5, but how is it faster than the Quad? What exactly makes the Intel faster than the G5? I am looking at the Apple specs of the Quad and to me, it looks like a really solid computer, especially for 2005.

2 Dual Core 2.5GHz PowerPC Processors
1MB Cache Per Core (4MB Total)
FSB 1.25GHz Per Proc
Up to 16GB DDR2 PC2-4200

So, what makes the G5 Quad, or even Dual Core/Dual Proc G5's so weak?



dukebound85
Jun 26, 2009, 10:47 PM
old tech from circa 2005 vs new tech in 2009 has a role

noodle654
Jun 26, 2009, 10:49 PM
old tech from circa 2005 vs new tech in 2009 has a role

Ohh...my mistake, when they first came out with the Mac Pro.

Andrew Henry
Jun 26, 2009, 10:49 PM
I never fully understood this topic really. I have always been interested in getting a G5, ever since they came out. I might be able to nag a Quad G5 for very cheap, but I have a question. I know that an Intel Core 2 Duo is faster than a G5, but how is it faster than the Quad? What exactly makes the Intel faster than the G5? I am looking at the Apple specs of the Quad and to me, it looks like a really solid computer, especially for 2005.

2 Dual Core 2.5GHz PowerPC Processors
1MB Cache Per Core (4MB Total)
FSB 1.25GHz Per Proc
Up to 16GB DDR2 PC2-4200

So, what makes the G5 Quad, or even Dual Core/Dual Proc G5's so weak?

You answered the question yourself... for 2005, not 2009.

SkyBell
Jun 26, 2009, 10:51 PM
It isn't... it's definitely equivalent then most of the Core Duo machines, and even some C2D's.

noodle654
Jun 26, 2009, 10:56 PM
It isn't... it's definitely equivalent then most of the Core Duo machines, and even some C2D's.

Well...how is it comparable to my 2.2GHz MBP...

The way I think of it, wouldnt the G5 Quad be faster than my MBP?

dukebound85
Jun 26, 2009, 10:59 PM
why would you get a g5 now? you will be forever stuck with leopard

dr. shdw
Jun 26, 2009, 10:59 PM
http://www.barefeats.com/quad12.html

noodle654
Jun 26, 2009, 11:05 PM
why would you get a g5 now? you will be forever stuck with leopard

What's wrong with Leopard? If I am able to get a G5 for very cheap, why wouldnt I get it?

iBookG4user
Jun 26, 2009, 11:12 PM
Well...how is it comparable to my 2.2GHz MBP...

The way I think of it, wouldnt the G5 Quad be faster than my MBP?

According to Geekbench (http://www.primatelabs.ca/blog/2009/01/mac-performance-january-2009/) the G5 will be slightly faster. So if it is a good enough deal and it fits your needs, go for it. But realize the limitations that you're buying a computer which will not be able to run the latest operating systmes and developers will slowly move to intel programs only.

voyagerd
Jun 26, 2009, 11:12 PM
The Quad G5 is faster, as per Geekbench scores. Since the computer is 4 years old, it doesn't have much future in it though. My G5 just acts as a table to put my MBP on currently. I'd compare the 4 core G5 prices with the earliest Mac Pro prices. Even the 2GHz Mac Pro beats the G5 by quite a bit.

MacBook Pro (Mid 2007)
Intel Core 2 Duo T7500 2.2 GHz (2 cores) 2836

Power Mac G5 (Late 2005)
PowerPC G5 (970MP) 2.5 GHz (4 cores) 3244

dukebound85
Jun 26, 2009, 11:14 PM
What's wrong with Leopard? If I am able to get a G5 for very cheap, why wouldnt I get it?

nothing

i just dont see the point in buying hardware that will no longer be supported

do what you want though

andiwm2003
Jun 26, 2009, 11:22 PM
there are people still using G4 Powerbooks and they run fine with leopard. If you get it really cheap (less than $250) then go for it I would say. It will work fine for another three years. However you might not get the newest software anymore because eventually developers will deliver Snow Leopard software only.

But for a few years it should be fine. Right now its twice as fast as my 2.4GHz MBP and 8 times as fast as my PB G4.:eek:

noodle654
Jun 26, 2009, 11:23 PM
The Quad G5 is faster, as per Geekbench scores. Since the computer is 4 years old, it doesn't have much future in it though. My G5 just acts as a table to put my MBP on currently. I'd compare the 4 core G5 prices with the earliest Mac Pro prices. Even the 2GHz Mac Pro beats the G5 by quite a bit.

MacBook Pro (Mid 2007)
Intel Core 2 Duo T7500 2.2 GHz (2 cores) 2836

Power Mac G5 (Late 2005)
PowerPC G5 (970MP) 2.5 GHz (4 cores) 3244

Thank you for these...I have a question though. It seems like per core, the Intel C2D is much faster than the G5 Quad, why exactly?

Ti_Poussin
Jun 26, 2009, 11:40 PM
I have own a G5 quad, and it's pretty damn fast, my iMac with a Core2Duo seem like a slow molasse after running for a years on those beast. As the speed point of view, the G5 can handle pretty much anything you can throw at him. It's fast bus system and multiple core make it a wonderful machine for running many heavy task at the same time.

The only bummer, is the support for Snow Leopard. But if you can get it cheap and don't mind Leopard or a 32/64 bit Linux, it's a good machine. Make sure to cheek for water cooling leak before buying, there was a problem on a part of the series.

If I could choose to have a Quad G5 or a core 2 duo, I would choose the quad G5, as for comparing it to a quad Xeon is another story, but different price range also.

California
Jun 26, 2009, 11:52 PM
My Quad and same late 2005 revision 2.3ghz Dual Core PM G5 with 11 gigs of ram and the Quadro video card run circles around my MB Aluminum 2.4 with four gigs of ram that I just sold. The geekbench scores on those lists rate them with stock, oem or limited ram, which is a shame.

The 2.3 is not quite as fast as the Quad of course but right up there.

If you don't care about Snow Leopard and can get a good deal, they are great machines.

I am VERY content.

richard.mac
Jun 26, 2009, 11:54 PM
upgrade the G5 with as much RAM as you can afford and the latest, fastest standard hard drive like the Seagate 7200.12 or WD Caviar Black then it will be a snappy machine.

the Intel processors are probably a bit faster than the Quad Core G5 in the Macs but its not a huge difference in everyday usage. a large difference wouldnt be noticed until you fully load the processor/s.

OrangeSVTguy
Jun 27, 2009, 12:12 AM
If you can find a quad for less than $700 than that is a very good deal. Like others have mentioned, check for leaks first and check often. High revving fans or kernal panics are typically the first signs of a leak.

The G5 will run Leopard just fine for many years to come. So what that it won't run the latest and greatest, if the current software is good and fast enough for you, then it will be good and fast enough for you a few years from now.

I'd say in maybe 4 years, the Mac Mini will absolutely smash any pre-intel machine as it will probably have 16 cores and support 128gb of memory. :D

Dr.Pants
Jun 27, 2009, 01:17 AM
I *bought* a Quad recently, and really enjoy it. Sure, a MacPro would be faster, but my budget shrunk due to some... unexpected tuition :o And RAID costs money, along with non-academic FCS2! I am in the process of upgrading it; insofar, its a very nice machine. I perfer it over the Intel iMacs I used in my visual communications class; I guess I am an expandability sucker :p

That's beside the point though - the point is I wanted to run Final Cut and a RAID array, and I just didn't have the money for a first-gen MacPro to put into my budget. A G5 sufficed everything I wanted. Sure, its not as powerful as some other machines, but it gets the job done better then a lot of the others, too.

As for the OS, all I can say is that on the update will 10.5 stop working? Nope - it will also run FCS2 for some time to come. In a few months I also plan to replace the conductive, corrosive coolant with a nonconductive noncorrosive one - just being a chem/physics geek/major, I want access to my universitys new labs to run some "extracurricular" tests.:D ((For the initiated, heat capacity, viscosity, and density in comparison of the original liquid to the replacement))

OZMP
Jun 27, 2009, 01:46 AM
2 Dual Core 2.5GHz PowerPC Processors
1MB Cache Per Core (4MB Total)
FSB 1.25GHz Per Proc
Up to 16GB DDR2 PC2-4200

So, what makes the G5 Quad, or even Dual Core/Dual Proc G5's so weak?

Then factor in my machine for similar price.

Processor Name: Dual-Core Intel Xeon
Processor Speed: 2.66 GHz
Number Of Processors: 2
Total Number Of Cores: 4
L2 Cache (per processor): 4 MB
Memory: 5 GB
Bus Speed: 1.33 GHz

Then add snow leopard wont run on your g5, will run on my machine, new 4870 will run on my machine, so OpenCL will make the Intel quicker again etc. Lots of apps no-longer run properly on PPC, Where they are Intel native(CS4 etc).

Must i continue? I had you at the front side bus and clock speed, before we even went to the new OS due in september and OpenCL that is brought with it :)

Its not them being weak, they are a decent machine, it is more that apps and OS are no longer written to be natively run on them. You may as-well be buying a machine and running OS9 or windows 3.1 IMO -> A dead technology.

I bought a G5 tower at the start of the intel transition, got it for a good price second hand, resold it once i had saved enough for my current machine. Even back then I was having issues with apps being for PPC.

SkyBell
Jun 27, 2009, 01:53 AM
Thank you for these...I have a question though. It seems like per core, the Intel C2D is much faster than the G5 Quad, why exactly?

Just a newer technology... things like that happen.


The Quad G5 is still a beast though. :D

300D
Jun 27, 2009, 03:58 AM
If I am able to get a G5 for very cheap, why wouldnt I get it?

The guaranteed-to-die liquid cooling system for one.

It seems like per core, the Intel C2D is much faster than the G5 Quad, why exactly?
1, its PowerPC. 2, its 4 year old technology. 3, the Intel is much more efficient.

ReanimationLP
Jun 27, 2009, 04:22 AM
The nice thing about these though is you can load it up with 16GB of RAM for less than 160.

Catfish_Man
Jun 27, 2009, 04:25 AM
Thank you for these...I have a question though. It seems like per core, the Intel C2D is much faster than the G5 Quad, why exactly?

There are many many reasons why this. I'll list a sampling of them, but there's hundreds (likely many thousands) of small reasons.

* Manufacturing process: the transistors
and wires in the Core 2 Duo are smaller (due to being made on newer manufacturing equipment), allowing reduced power usage and/or increased speed. Intel's also made some innovations with the materials used recently (google "high-k dielectric").
* Load/store reordering: the C2D has a lot of flexibility in what order it loads data from memory, allowing it to reduce the amount it has to wait. It can even do things like start loading some data ahead of a store, then cancel and restart the load if it turns out that the store was to the same address (overwriting the data that would have been loaded).
* The G5's instruction issue limitations: The G5 is very picky about how instructions are grouped, and programs that don't take this into account sometimes end up missing out on a good bit of its speed.
* Bigger caches: another benefit of smaller transistors is just that you can use the extra space freed up by them to add things like gigantic caches. Intel also seems to be able to design caches that are both very fast and large. I don't know how they manage that.
* The G5's rather high memory latency: While the G5 had tons of memory bandwidth, its latency was pretty awful.
* Branch prediction: C2D has a very advanced branch predictor including a loop end predictor and assorted other clever ideas
* The G5's slow integer units: Even the simplest integer operations take two cycles to complete on a G5, making it difficult to schedule some code for optimum throughput (you have to interleave dependent integer math with other operations).
* Memory prefetching: Both chips do pattern recognition in order to predict loads, but the C2D implementation of it is apparently extremely good.


Overall, my expectation would be:
* The C2D will absolutely destroy the G5 for tasks like compiling, or running javascript. These are memory latency sensitive, integer/branch sensitive, and use caches well (strong temporal locality).
* The G5 will compete well on things that emphasize bandwidth over latency, straight-line code over branches, and floating point math over integer. In particular, vector code (altivec for the G5, sse 1-4 for the C2D) should be competitive.
* Most day to day applications either don't use the CPU heavily (common) or fall somewhere in between these extremes, but significantly more towards what the C2D is good at.

Sadly for the G5, most of the things it's good at happen to also be the things GPUs are good at. The things it's bad at tend to be the day to day tasks of using a computer. Not unexpected for a cut-down server chip I suppose.

Umbongo
Jun 27, 2009, 08:36 AM
There are few things that have been touched on here that would really make me think twice.

Well known issure of liquid cooling leakage: This completely rules out any possibility for me.

Lacking graphics card options: Even if your workflow isn't GPU based, its nice to have performance if you need it. Many applciations are going to be utilizing this more in the future.

PPC: Performance wise it may still be enough, but its not just Apple operating systems that are going Intel only. Most software will go this way.

Out performed by 2GHz 2006 Mac Pro: This is perhaps more a budget one, but you can find these cheap from time to time. Like close to $1,000. Now we don't know your finances or how much the G5 is available for, but if you are talking ~$700 then for several hundred more you can get a lot of expandability (upgrade to 8 cores for under $600 easily, power graphics card options) and future support.

I'm sure there are plenty of people who have slower systems than the G5 you are looking at that will last them many more years, and some who would be fine with such a system now. It's not like it got slower since 2005, just newer software is more demanding and you may be able to better use the money.

Tesselator
Jun 27, 2009, 09:24 AM
I think it comes down to the familiar price|performance ratio thing again. :)

How much are you getting this G5 Quad for noodle654?

As for the leaks just replace the water with Silicon Oil and then if it ever does leak all you'll have to do is wipe it up. No damage will occur.

noodle654
Jun 27, 2009, 09:43 AM
There are many many reasons why this. I'll list a sampling of them, but there's hundreds (likely many thousands) of small reasons.

* Manufacturing process: the transistors
and wires in the Core 2 Duo are smaller (due to being made on newer manufacturing equipment), allowing reduced power usage and/or increased speed. Intel's also made some innovations with the materials used recently (google "high-k dielectric").
* Load/store reordering: the C2D has a lot of flexibility in what order it loads data from memory, allowing it to reduce the amount it has to wait. It can even do things like start loading some data ahead of a store, then cancel and restart the load if it turns out that the store was to the same address (overwriting the data that would have been loaded).
* The G5's instruction issue limitations: The G5 is very picky about how instructions are grouped, and programs that don't take this into account sometimes end up missing out on a good bit of its speed.
* Bigger caches: another benefit of smaller transistors is just that you can use the extra space freed up by them to add things like gigantic caches. Intel also seems to be able to design caches that are both very fast and large. I don't know how they manage that.
* The G5's rather high memory latency: While the G5 had tons of memory bandwidth, its latency was pretty awful.
* Branch prediction: C2D has a very advanced branch predictor including a loop end predictor and assorted other clever ideas
* The G5's slow integer units: Even the simplest integer operations take two cycles to complete on a G5, making it difficult to schedule some code for optimum throughput (you have to interleave dependent integer math with other operations).
* Memory prefetching: Both chips do pattern recognition in order to predict loads, but the C2D implementation of it is apparently extremely good.


Overall, my expectation would be:
* The C2D will absolutely destroy the G5 for tasks like compiling, or running javascript. These are memory latency sensitive, integer/branch sensitive, and use caches well (strong temporal locality).
* The G5 will compete well on things that emphasize bandwidth over latency, straight-line code over branches, and floating point math over integer. In particular, vector code (altivec for the G5, sse 1-4 for the C2D) should be competitive.
* Most day to day applications either don't use the CPU heavily (common) or fall somewhere in between these extremes, but significantly more towards what the C2D is good at.

Sadly for the G5, most of the things it's good at happen to also be the things GPUs are good at. The things it's bad at tend to be the day to day tasks of using a computer. Not unexpected for a cut-down server chip I suppose.
Thank you!! This is exactly what I was looking for, the tech talk. You answered my question completely. Depending on how much I can work down the price, I might end up buying a Mac Pro, Rev A to be exact. Too bad SL will drop PowerPC support, if it wasn't I would buy a G5. I will see what happens and I will let you guys know. Thanks everyone for your help.

dr. shdw
Jun 27, 2009, 12:13 PM
Thank you!! This is exactly what I was looking for, the tech talk. You answered my question completely. Depending on how much I can work down the price, I might end up buying a Mac Pro, Rev A to be exact. Too bad SL will drop PowerPC support, if it wasn't I would buy a G5. I will see what happens and I will let you guys know. Thanks everyone for your help.

Why get a MP (around the same speeds) if you already have a MBP?

Black107
Jun 27, 2009, 12:25 PM
I had a quad G5 from when they first came out in late 05. I remember I wanted it as soon as possible so I didn't custom order it with the better graphics card at the time the 7300GT cause that would have added 3weeks to a month to the delivery time. I never ended up upgrading the card for some reason, likely due to the expensive yet mediocre options available, so I have been using it with the Nvidia 6600LE up until last week when I got a Octa 2.66 Mac Pro with an Nvidia GTX 285.

There is no comparison.

While the G5 is a very competent machine even today under leopard, the Mac Pro is just *that* much snappier in my opinion, and worth every penny. Now the G5 was very competent in Photoshop/Illustrator/After Effects (I ran it with 4.5GB of ram, which now a days you can upgrade even higher for very cheap), but after 3.5 years I felt it was time for a new computer that would be there for me in the future as newer technologies come out (10.6 for example), plus the G5 was missing out on newer software that is written for Intel only. I have an early 07 macbook pro with 2GB of ram and it tends to get more easily overwhelmed than the G5 does, but I figure this is more due to the ram (the machine has a maximum of 3 :( )

Bottom line, I bought my quad g5 right when they came out in late 05, and its lasted me for 3.5 years (and could last me for at least couple more, provided the cooling system doesnt fail) but I just felt for me it was time to upgrade and I wanted an intel, and I figure this mac pro will last me at least 3.5 years as well.

Good luck on your decision, but if it were me, I'd see if I could get into a second gen mac pro at the least so you're a little more future proofed.

One more thing, as I mentioned briefly above, the quad g5 was the only g5 model that used a liquid cooling system for the CPUs. From what I've heard more than a few have had those units go on to fail/leak. If I remember correctly, there were two contractors for that part, so some G5s used an AC Delco model, and some used a part from another one. I cant remember which one was more proned to failure, but you might at least want to do the leg work on this and see if its correlated to serial number or anything. Its just something to keep in mind given that some of these things are approaching 4 years old. For what its worth, mine never experienced any problems aside from an HD failure.

noodle654
Jun 27, 2009, 01:20 PM
Thank you everybody for your help. My friend wanted $1000 for the Quad and I said no thanks. I'm most likely going to buy a Rev A or B Mac Pro soon, so we will see what happens. I really appreciate all the help, especially the tech talk of th Quad G5.