The Mac G5 kicks ass

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i agree alex,..this is a nice discussion, thanks to this mj_1903 guy mostly. ..i never thought my post about my P4 kicking G5's butt would actually make him tick. ofcourse it'll kick my 2.5g's ass, don't take things too seriously,bro...its not healthy.in addition to that. this is my last post on this thread,..as this is an endless debate. so mj_1903, you may post all you want... and i have a good one m8!
 
But why bother...the G5 runs native 32bit operating systems and apps without a hitch and it runs them damn fast as well. 64bit really is to address the 8Gb of memory.

actually 64-bit processors are made for addressing 16 exabytes of memory, not 8 gigabytes (an exatbyte is 1 billion gigabytes) i will post a link in a few to the article where this is explained, ciao

*edit* here is the article about 64-bit computing:

http://www.pcworld.com/news/article/0,aid,111771,00.asp
*edit*
 
mj_1903 said:
Yup, I know...but at this time the G5 can only handle 8Gb of RAM.

which is funny, because there are 32-bit intel processors that can handle up to 64 GB of ram

and the claim that apple makes about the G5 being the worlds first 64-bit processor is bs, because AMD already had one released apple may have the worlds WORST 64-bit processor (lol, just a joke at apples expense) but definately not the first
 
Just to enlighten me, which Intel processor that is 32bit can address 64Gb or RAM? I have never heard of a processor being 36bit although there are 42bit interconnects to enable it to address more than 4Gb of HD space.

As for the first on the market...Apple made a dubious point there but then again they are relatively correct. All 64bit chips so far have been workstation...Apple have made a workstation at consumer prices. The AMD Opteron has not been released yet so it cannot even hope to take the crown. If you wanted to the Itanium could possibly take it...but I see no consumer OS running on it.

Then again, Apple does not make the G5, IBM does and IIRC IBM stated that the PPC 970 (G5) was the first consumer modelled 64bit processor.
 
in answer to your question, mj, wither the P4 or Xeon is capable of addressing up to 64GB of ram(it doesnt have to be a 36 bit processor as 36 x 2 doens not = 64, it is 32 x 2, 36 bit doesnt even make sense as most computer specs are based on the powers of 2 which 36 is not.

i have been reading some of the tests on apple's website in which apple clams that it "blew away" the P4 but yet in integer calculations, the P4 was 10% faster (quite a bit, when youre considering data processing) i will read some more and post again later
 
"in answer to your question, mj, wither the P4 or Xeon is capable of addressing up to 64GB of ram(it doesnt have to be a 36 bit processor as 36 x 2 doens not = 64, it is 32 x 2, 36 bit doesnt even make sense as most computer specs are based on the powers of 2 which 36 is not."

Oi? To address 64Gb of RAM you need a 36bit addressing system.

2^32 =~ 4 billion
2^36 =~ 64 billion

Hence the need for a 36bit addressing system to address 64Gb of RAM. As you stated earlier

2^64 =~ 16 x 1000 x 1 billion

So I can't really see how that answers my question.

A 32 bit processor (Pentium class, Xeon class) can only address 4Gb of RAM and that is all. Period.

As for the website, quickly note that there is no such machine as a single 2ghz G5 as the test was done against and you will see that the int test was simply to benchmark fairly with a 3.0ghz processor. As you will note, the P4 was rudely hammered in the floating point arena by ~24%. Add a second processor as the machine has and there is an even slighter difference.

Obviously as the spec benchmarks don't support Altivec (the PPC 970's special instruction set which contains 128bit instructions with 128bit memory pipelines) then we are not seeing the full story for optimized applications. Altivec on the G4 generally gave a 3.2-8x faster performance than standard code. On the G5 we will probably see a 2-3x faster performance (as was seen in the HMMer test on the performance page.
 
mj_1903 said:

As for the website, quickly note that there is no such machine as a single 2ghz G5

if there is no such machine, howw could they have possibly run the test?
 
"if there is no such machine, howw could they have possibly run the test?"

On boot the firmware of the Mac can be changed to disable a processor. The firmware can also control CPU speed (as in Ghz), bus speed, voltage and other hardware settings such as PCI and AGP support. It is also used to control Altivec enabling.

You can easily change the firmware of a machine on the fly, for instance to put one CPU in a powermac to sleep if your machine is at low loads or to change the mhz so as to draw less power.

I know I used a firmware hack to bring my FSB speed to 167mhz rather than the 133mhz it was shipped at to give make my machine a Dual 1.06Ghz PowerMac rather than a Dual 867. Its very useful and saves soldering the motherboard sometimes.

If you want to research it more, look at Openfirmware which I believe was designed by Sun and NeXT.
 
64 GB of RAM is accessable by a 32 bit x86 chip called the Xeon MP. The only way you could get 64GB though is with a 16 chip Xeon MP array, where each chip, being 32 bit, addresses its own 4GB of RAM.

But that is multiple processors. No individual 32 bit processor can address more than 4GB of physical RAM.

Just thought Id help clear that up.
 
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