My ignorance.
Okay, I'm a newbie on AI and a neophyte to the world of computing. But what the heck is Front Side Bus, what does it do??? What is 32bit processing and 64bit processing really. Does that equate at all to Photo Shop performance? What exactly makes the 1.8Ghz 970 comparable to the 3Ghz P4?
For the ignorant, like myself, larger numbers for processing power make immediate sense, and for those aquaintted to reading on, like myself, know that a lot of the times the numbers are only half the story. Please, explain it as if you were explaining it to your 13 year old sister.
For the ignorant, like myself, larger numbers for processing power make immediate sense, and for those aquaintted to reading on, like myself, know that a lot of the times the numbers are only half the story. Please, explain it as if you were explaining it to your 13 year old sister.
Comments
Originally posted by LiquidR
. . . Please, explain it as if you were explaining it to your 13 year old sister.
That's easy, because I'm just learning some of this myself. Maybe an expert will correct my mistakes here.
Front side bus is the normal bus that connects a processor to other stuff, like the main memory. Backside bus is for small amounts of special high speed memory, called a cache.
32 bit and 64 bits are the size of the "registers" in the processor. The bigger the register, the bigger the numbers that the processor handles quickly. If the register is too small for the number, the processor takes longer to work on it. For most stuff we use a Mac for, it will make no difference. For stuff that uses big numbers, it will help a lot.
As for the MHz of a processor, or clock rate, think of an engine. One factor is its RPM. The higher the RPM it can turn, the more horsepower it has. There are other factors, like displacement, or its cubic inches, which also affect horsepower. It turns out that the cubic inches are more important than RPM. Same is true for processors. Clock rate is only factor in determining the computing power of a processor. You can tune a small engine to run at very high RPM, but a really big engine will out-perform it.
Front side bus is the normal bus that connects a processor to other stuff, like the main memory. Backside bus is for small amounts of special high speed memory, called a cache.
If you change the word "processor" in that to "Northbridge" Then you just gave a fine example of the look aside bus. The frontside bus is what connects the processors to teh north bridge.
With the 64 and 32 thing, Its a really big software issue and has to do mostly with the size of variables and How big a variable your processor can process. Having a 64 bit processor will really help those scientific apps that do vast amounts of number crunching.
Snoopy had a good example for this but here is mine just for sh¡ts and giggles:
I like to think of it like this; Every processor has a pipline, Some have multiple piplines as found in some AMDs. A pipline is a set of instructions for the processor to carry out in "processing the data" See the G4 I am on (7450) has a 4 stage pipline so its like a 4 mile stretch of road and the data travels down it at 533 MPH. Compare that to a P4 whitch has something like 30 stages to the pipeline but goes a hell of a lot faster.. Understand? Now their are other things that come into play like Speed of your RAM quality of your northbride IE hypertransport, RapidIO, HD speed, Pipeline depth. Yadi yadi but I didnt feel I needed to go into that. If your interested in learning more feel free to pop me a PM.
Also I been up all night so If I screwed anything up feel free to correct me.
Originally posted by Mount_my_floppy
If you change the word "processor" in that to "Northbridge" Then you just gave a fine example of the look aside bus. The frontside bus is what connects the processors to teh north bridge. . .
Okay, I have a question. Just for keeping it simple, can't we consider the front side bus as connecting the CPU to most things on the motherboard, but that it goes through a helper chip? Also, I thought Apple called the chip a system chip or memory controller or something? I'd just like to know. I also hear that some CPUs may have a memory controller on board. These would be lower performance CPUs, but the bus may still be called the front side bus, no? (I need to take Introduction to Microprocessors, CS 101.)
One more comment on 64 bits. It lets the CPU connect to over a billion times more memory. It took about 20 years to go from 128 KB of RAM to 256 MB, for a typical Mac, an increase of about 2000 times as much RAM. It will take a very long time indeed before we need more than a billion times as much RAM as we use today.
Originally posted by snoopy
Okay, I have a question. Just for keeping it simple, can't we consider the front side bus as connecting the CPU to most things on the motherboard, but that it goes through a helper chip? Also, I thought Apple called the chip a system chip or memory controller or something? I'd just like to know. I also hear that some CPUs may have a memory controller on board. These would be lower performance CPUs, but the bus may still be called the front side bus, no? (I need to take Introduction to Microprocessors, CS 101.)
One more comment on 64 bits. It lets the CPU connect to over a billion times more memory. It took about 20 years to go from 128 KB of RAM to 256 MB, for a typical Mac, an increase of about 2000 times as much RAM. It will take a very long time indeed before we need more than a billion times as much RAM as we use today.
You are right, the FSB is there to connect to a chip wich itself connects to the other things on the motherboard.
This chip (called northbridge) has in it a memory controller which is responsible to exchange data with the memory. So when the CPU need to read from/write to memory, it ask the northbridge.
Some processor have integrated memory controller, like the new Opteron of AMD. It is far from a low performance CPU, I can assure you
I think the Alpha (probably the most powerfull CPU up to now) was supposed to have also that, but since it has been bought by Intel, this architecture is going to die
About 64bits, its main advantage is to handle more than 4Go of RAM. Its second advantage is to handle 64 bits integers, but these numbers are only used in specific application (like cryptography). In contrast, the floating point units of current CPUs handle 64bits data for years (well x86 CPUs has a 80bit FPU since the 486).
So for the majority of applications, you won't see an improvement.