Shoutbox

What's about the 64 technology? I've read lots about it but what's the real advantage. Does it work twice as fast then the 32 processors? And what is best: 2*2.8Ghz 32 Pentium processor or 3700+ AMD 64 processor?

The AMD proccessor becuase if im not wrong having two processors does not mean having double the speed.
Having 2 means that once one is full it then goes onto the other proccessor, it doesnt use them togeather at one time. So in actual fact it's much more lkely that you wont use the second one as much as the first one becuase you RAM does the most work not the CPU as in for running applications,games etc...
Please correct me if im wrong

So it's not that in future we will all be using 64 processors? So if u buy a new pc i shouldn't be looking like i should better buy a 64 so it will be compatible in future... so the 2*2.8 would be fine too? Eventual that is 5.6Ghz.... so it's better then the 3700+ 64 bit...?

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Originally posted by Nathan
The AMD proccessor becuase if im not wrong having two processors does not mean having double the speed.
Having 2 means that once one is full it then goes onto the other proccessor, it doesnt use them togeather at one time.

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I'm afraid you are wrong
Having two processors means that your PC can literally do two things at once. Windows will try to keep both busy as much as it can, but you still won't get double speed, due to memory bandwidth, bottlenecking, concurrency issues...

Personally, I'd go for the AMD64. The speed won't be much lower than a twin processor machine, it'll be far far cheaper, and it'll ease the transition to 64-bit computing.

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Originally posted by raceprouk

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Originally posted by Nathan
The AMD proccessor becuase if im not wrong having two processors does not mean having double the speed.
Having 2 means that once one is full it then goes onto the other proccessor, it doesnt use them togeather at one time.

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I'm afraid you are wrong
Having two processors means that your PC can literally do two things at once. Windows will try to keep both busy as much as it can, but you still won't get double speed, due to memory bandwidth, bottlenecking, concurrency issues...

Personally, I'd go for the AMD64. The speed won't be much lower than a twin processor machine, it'll be far far cheaper, and it'll ease the transition to 64-bit computing.

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Tnx

I did some researching and i got some information about 64 systems. It can process larger numbers (data numbers). That means that Word, which has needs low calculation, won't work any faster. But processes which need a lots of mathematics and calculation will work faster. For example copy-paste will work at least twice as fast. Programs that are explicit written for 64 systems will be coded with large numbers, so it will eventual process faster with a 64-bit processor.

Now, there are no many programs written for 64, and they will rise slowly in the future. That means that once it's all 64, my 3700 64bit processor will already be outdated.

The 2*2,8 Ghz processor in comparisation will be faster, because it has the same speed for 32 applications than a 64bit processor would have fot 64-bit applications. So it's more interesting to take the dual-processor, isn't it?

To make a long story short: a 64-bit processor on 3,7Ghz will work as fast as a 32-bit processor on 3,700Ghz when using 32-bit applications, while the 2*2.8Ghz processor will actually work on 5.6Ghz with 32-bit applications. Which is the best choice, as we will all be using 32-bit applications for the next years, won't we? (pls correct me if i'm wrong)

Actually, I'm not 100% sure that 64 bit processors actually use larger numbers, I believe this to be a common misconception.

Let me show you my reasoning:

Maximum Addressable Memory = 2 ^ Size of Address Bus
Maximum Size of Memory = (2 ^ Size of Address Bus) * Size of Data Bus

Now, the Maximum Size of Memory in a 32 bit machine is 2^32 bytes, aka an Address Bus size of 32 bits and a Data Bus size of 8 bits (1 byte = 8 bits).
Also, the Maximum Size of Memory in a 64 bit machine is 2^64 bytes, aka an Address Bus size of 64 bits and a Data Bus size of 8 bits.

Btw, if you didn't know, the Address Bus is used to address memory locations in RAM (memory is used to refer to working memory, ie RAM, not backing storage, such as the space on a Hard Disk Drive), and the Data Bus transfers data to and from the processor.

So, as you can see, a 32 bit processor has an 8-bit data bus, but so does a 64 bit processor. So a 32 bit processor in essence is no slower than a 64 bit one.

BUT: A 32-bit processor is limited to 4GB of RAM, whereas a 64-bit processor is limited to something like 16EB. Now, in todays world, most PCs only have 1GB of memory modules installed so there isn't a problem.

64-bit processors are actually slower when it comes to things like pointers, but that's a really technical thing, you don't need to worry about it.


So basically, on a 32vs64 bit processor system, there is no difference in current machines. But the instruction set differs between a 32bit AMD and a 64bit one, and these extra instruction sets give the 64bit processors an advantage. And it's always been said that MHz for MHz, AMD processors are much faster (the actual number (such as 3700+) for an AMD processor isn't it's actual clock speed, it's the comparison in speed to a P4 processor).

Now, if I were basing my choice, I'd be stuck. AMD have just introduced the AM2 socket, which means that the 939-pin processor line will be effectively dead within 2-3 years, and people will be using the 940-pin socket. Of course, with a 939-pin motherboard you can still upgrade to things like AMD's X2 4800+ processors, as those are designed for 939-pin motherboards atm.

I think Intel have started releasing 64-bit processors, so buying a 32-bit motherboard now may limit your options for upgrade even closer in the future.

Update: Forgot to mention cache size, I think AMD 64s of that line have 1MB L2 cache and the Dual-P4s have 1MB per core, so the P4 would be faster in that capacity. (Cache is lightning fast SRAM stored close the the processor and stores commonly used instructions).

So yo would go for intel's processor? (The 5.6Ghz) it is 100$ more expensive than the 64 3.7, but that's no problem. Is the intel much faster then?

Is it a double processor or a double core?

If it's a double core, I would go for the intel, else I would go for the AMD.

And like said before you can't add up te Ghz'ses. it will be a double processor 3.2 Ghz processor, but that doesn't mean it will double the Ghz'ses, the fact that you think this, is because of the misconception that more ghz'ses means faster, but this is not true.

With a double(core/processor) the computer can run 2 threads at the same time, this can mean (in the simpest form) two applications or 2 processes of the same application at the same time.

A processor can only do 1 thing at a time, but processors use process scheduling to switch between processes/threads, this happends so fast that you won't notice, but with double core/processor, this means it can do it really simultaniously, causing the increase in speed.

But I wouldn't go for a double processor, because that will be harder to switch upgrade processors later and stuff.

So to make a long story short. If it's a dual core i'd go for the intel else i'd go for the amd.

Btw, on normal 32-bit windows, afaik you can't run 64-bits applications. You'd need 64-bits windows/linux whatever.

This is a question to which there is no simple, easy answer.   

The dual core Intel does not amount to "5600" or twice the performance of one 2.8GHz core.  The reason for this is the instructions making up computer code must be executed in order.  This sequence of execution is called a "thread."

When you run several programs on a computer with a single processing core and they appear to be all running at the same time, that is not what is really happening.  Each program has at least one thread.  The processor quickly switches between threads, executing each one at time.  Because threads are switched many times per second, you don't notice it -- just like you don't see individual frames when you watch a movie.

With two cores, you still can't have both cores working on the same thread and getting it done twice as fast.  However, both cores can each be working on different threads, at the same time.

Let's say we have a program that uses only one thread and performs some long calculation.  If it takes 10 seconds to complete on a single 2.8GHz core, it will still take 10 seconds to complete with two 2.8GHz cores -- because the single thread can run only on one core at a time.

If we run two instances of the same program together, with a single core they both might complete in 20 seconds (the processor time will be divided between them).  However, with two cores, they both might still complete in the same 10 seconds it took to run just one.

If we were able to design our program to evenly divide the workload internally and run two threads -- yes, one program can internally use multiple threads -- then a single instance of the program would still take 10 seconds on single core, but might complete in 5 seconds with two cores.

What if we can't separate the workload evenly?  Let's say 70% of our calculation has to be done consecutively, in a single thread.  Then one instance of the program, with two cores, would take 7 seconds. 

Some applications use multiple threads internally, some do not.  Some are able to split the workload evenly, some are not.  This gets very complicated very fast, after you factor in the Windows operating system itself running multiple system threads along with your applications, at all times -- and the fact threads may have to wait on each other for things like reading and writing files to disk.

Andrew did a good job explaining the present limitations of 64 bit architecture and these are the limitations of dual cores.   You are probably now more confused than ever. 

If it helps any, the benefit of the second core is usually estimated to be 20-50% depending on the software mix you are running.  Going with that figure leaves both of your choices looking about equal.