diff between single core pentium 4cpu @3.2ghz and stock dual core at say 2.4ghz

[techgamer]

To my understanding from reading... just comparing cpus more ghz means faster computer speeds, ie will run programs faster. More core cpus means better multitasking because you have more 'brains' doing the processes. Is this accurate? Or do more cores also account for some 'linear' task speed ?

So if this is true, it might not be necessary to upgrade a cpu for faster game play if you wont have as much ghz?

 

[Markfw]

First not all cpu's are created equal. A 3.2 P4 would equal about a 2.2 A64, and that is about equal to a 1.6-1.8 Core2. One 2.4 Core2 core would equal at least a 4.8 P4 (or better) and then 4 of those ? (quad-core) thats a lot of power.

 

[BladeVenom]

You're understaning is mostly wrong. Clockspeed is only a reliable indicator when everything else is the same. More CPUs can increase a single programs speed, but it depends on how well multithreaded the program is.

A car analogy would be comparing engines by RPM. Which would move your car faster a small four cyclinder engine at 8,000 RPM, or a big block V-8 at only 6,500 RPM?

 

[InflatableBuddha]

Have you heard of the "megahertz myth"? More is not always faster. You can only compare clock speeds within the same architecture (i.e. P4 to P4 or C2D to C2D.) As soon as you compare across processor types, many other factors come into play:

Amount of cache memory
FSB
Multiplier
Pipeline length

etc.

Assuming a single-threaded application, a lower clocked Core 2 Duo will annihilate a Pentium 4. The C2D has a short pipeline and more cache memory, so it can send large batches of instructions down a short pipeline, less frequently. Comparatively, the Pentium 4 sends fewer instructions down a much longer pipeline, so to compensate, it has to send instructions far more frequently (hence the higher clock rate).

At a certain point, there are heat limitations. You can only run a processor so fast; otherwise it starts to overheat. Since the C2D runs more efficiently on each clock cycle, it doesn't need to be clocked as quickly to achieve the same results.

You're spot on about multi-core cpus being better at multitasking. They also shine in single applications that use multiple cores.

This is very much a layperson's explanation, as I'm not an engineer.

 

[techgamer]

Thank you for clearing things up. I didnt have a great understanding of it, but you guys made sense. I think what confused me was reading a post comparing an Amd x2 and a single core 64. The individual cpu chips were the same, but obviously the x2 was two of them. And they were saying that just throwing in an additional cpu didnt make a huge difference for most applications. So I think I took that and made a general analogy from it. But I understand the differences better now.