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thanks for watching Techquickie click the subscribe button then enable

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notifications with the Bell icon so you won't miss any future videos it's no

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secret that marketers really like numbers whether it's horsepower on a car

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screen size on a TV or the number of items on the buffet there's this general

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idea that people are drawn to large numbers and computer processors are no

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exception if you're shopping for a new system it's pretty easy to find

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retailers that prominently listed the processors gigahertz there's just one

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small problem it's basically an utterly meaningless metric these days and has

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been for at least the last 10 years now we touched on why you shouldn't just go

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buy raw speed when you're buying a processor in this video but we're gonna

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go into it in a little more detail today first off speed in megahertz or

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gigahertz measures how many clock cycles a CPU goes through each second and a

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cycle is basically what happens when an electrical pulse hits your CPU allowing

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it to execute instructions and keep its activity in sync with the rest of your

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system so this means that a processor rated at 4 gigahertz can handle a

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billion more cycles per second than one rated at 3 what's simple enough to

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understand but things get more complicated when you consider what

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happens during a clock cycle one big

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determining factor of a CPUs performance is how many instructions that can

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execute per clock cycle modern

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processors can work on more than one instruction at a time - thanks to

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pipelining which you can think of as being similar to how an electronics

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factory can turn out a huge number of smart phones per day even though it

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might take a long time for one phone to make it all the way through the assembly

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line so different stages of production are pipelined to take place

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simultaneously so that the guy that installs the screen isn't constantly

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waiting around for the next phone to work on pipelining in CPUs is similar in

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principle but quite a bit more complicated and engineers use different

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methods to allow the processor to chop up instructions into parts that can be

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worked on simultaneously or even combine

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smaller operation to complete them in fewer cycles increasing efficiency

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exactly how this gets accomplished depends on the specific

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microarchitecture of the processor which can learn more about up here but

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bringing things back to the topic at hand it means that because the number of

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instructions per clock cycle and the pipelining efficiency can very enormous

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ly between CPU brands and even the individual models from a single brand

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clock speed can end up being very deceiving CPUs also need to be able to

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read ahead on the page so to speak to work efficiently modern programs aren't

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all that linear and need to be able to respond to many different user inputs

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quickly I mean just think about how fast you expect your PC to show you the right

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thing after firing your weapon after someone else throws a grenade in a high

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budget video game so CPUs are designed to examine out of order instructions and

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make sure that they're executed such that they don't interfere with other

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parts of the program as well as to anticipate what instructions might be

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needed next a feature called a branch prediction CPUs with better branch

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prediction can have significantly better performance and again this is something

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you simply won't be able to determine just from looking at the clock speed and

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there are many other factors that tie into the performance as well like the

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type of RAM that is supported the types of instructions that are supported

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remember with MMX and CPUs can come with

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different types and amounts of cache memory you can learn more about it up

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here but basically it's this super fast memory that stores small pieces of data

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that the CPU thinks it will need in a hurry so a processor with a well

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implemented cache can fetch things it has to work on much more quickly finally

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if you're working on CPU intensive tasks like video encoding or file compression

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having many cores to spread the workload

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out and crunch more data in parallel can speed things up more than a clock speed

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boost now don't get me wrong clock speed shouldn't be ignored completely if it

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was totally irrelevant there wouldn't be a thriving community of overclockers

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trying to squeeze as many megahertz as they can out of there chips for dem

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performance gains and it can be a useful indicator of performance as long as you

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are only using it to compare CPUs with the same microarchitecture features and

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number of course or if you are compensating appropriately for the other

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differences that exist the point is just that it shouldn't be a huge factor in

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your buying decision just like you probably shouldn't choose a car based on

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how many cupholders it has that is unless you really like fast food

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gonna have that links below and enter Techquickie and how did you hear about

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