How does a dual out perform a single core processor

deaaaan

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Nov 2, 2009
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Ok so I'm running an older laptop (IBM R50) and It says it has a 1.6 ghz processor (intel centrino) Now I know that a dual core is better than a single because it's two processors in a single one, and a quad core is four, but I wanted to know why a newer IBM is only running at 1.8 ghz even though they are duo and quad core. Shouldn't it have twice the processing speed?

I don't use the computer for intensive gaming at all, and was just looking into getting a new one.
 

B-Unit

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Oct 13, 2006
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It has twice the processing speed because there are now 2 CPUs under the hood rather than one, each running at 1.8Ghz. The actual processing speed is not determined by raw Ghz, but rather by the architectural features and abilities of a particular CPU. A 1.8Ghz Core2 will run circles around a 1.8Ghz Pentium4, even tho they both run at 1.8Ghz.
 

ulysses35

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Its a little misleading to say its twice as fast, as each core may run at 3.0 ghz (E8400) but in the real world you just have two cores at the same speed.

Most games cant make use of a second (or third / fourth) core because the way it is coded.

Programmers are gradually making use of extra cores so in recent applications and some newer games you might see a performance jump.

Multi Core systems are much much better at multi tasking.... I have an i7 920, running windows 7, while burning a DVD and running email, internet etc with no lag.

 
Its not just speed, its core usage (how much of the additional cores are used), and how efficant the CPU is overall. For example, a 2.4GHz Pentium 4 was slower then a 2.4Ghz Athlon, as the Athlon did more work in the same amount of time.

The analogy: You can either carry a little bit back and forth and move quickly, or carry a lot at once but go at a slower overall speed.
 

uh_no

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in the architectural world, speed is currently measured in IPC, or instructions per cycle, which represents how well the processor can exploit parallelism inherent in code (and how many threads it can run simultaneously) This number, multiplied by cycles/second gives the instructions per second, which is the 'overall' speed.....therefore both clock speed and IPC are the main determining factors of how fast your CPU can do 'things'