What makes a CPU fast?

[DanielTheBest]

Hi guys. 

So I know what CPU's are good compared to other ones, but I have never fully learned what makes a CPU fast.

At the moment, the only aspects that I know that make a CPU fast is how many cores it has, if it has hyper threading, and the clock speed.

Thanks in advance, 

Daniel.

[Shd0w2]

I believe that the cache can affect performance in certain cases.

[Cubit481]

Hi guys. 

So I know what CPU's are good compared to other ones, but I have never really learned what makes a CPU fast. 

All I know at the moment is how many cores it has, if it has hyper threading, and the clock speed.

Thanks in advance, 

Daniel.

number of transistors it has...how quick can each transistor can pass information from one to the another...how close and small is the size of the transistor...that is what basically the idea of lowering the nanometers in the manufacturing process is about...

[MegaDave91]

All the Jiggahertz

[Createinator]

Higher Clock Speed/ Boost Clock, More L1, L2 Cache and most importantly being made by INTEL

[Meteora]

overclocking the already existing performance for more ghz! And less but more powerful cores(intel) makes it faster.

[ericlee30]

All the Jiggahertz

It's jiggawattz lol

[Shd0w2]

It's jiggawattz lol

sorry to correct yalls, but its called jiggabeetz.

[ericlee30]

sorry to correct yalls, but its called jiggabeetz.

Well blow me over Dr. Brown,now thats fast

[Akolyte]

The clock speed as well as the core speed.  The core speed really is not something you can just determine by looking at a cpu specs, dont quote me on that though.

 

But right now Intel cpus have the speed, AMD cpus have the clock speed but the clock speed doesn't justify the performance of Intel's fast cores.  Probably AMD will catch up soon though

[samuel]

The amount of instructions executed per second. That's all of it! It gets alot more complicated with multithreads and stuff but fundamentaly, a "fast CPU" opens the thing, renders the thing, closes the thing, does the given job generally faster.

Clock speed, the size of caches, a larger TDP, even the core count are all tricks to increase that IPS.

[Socratic]

Go faster stripes and LED's?

[Recon-UK]

Cache latency aswell as the actual platform the CPU is going to be working on.

 

A CPU needs to be able to do multiple instructions per second today, and this is not soley dictated by the clock speed it runs at.

 

Efficient design is where it matters.

 

If AMD's FX line were tighter on latency, and had a better platform to use, it may well be just as good as Sandy Bridge or maybe better, but that simply never happened at the time.

[Faa]

CPU monopoly is all about IPC, should say enough about what makes a cpu fast.

[ErickS89]

They have the need for speed!

 

Cache and Higher clock speeds make the cpu go fast.

[i_build_nanosuits]

The main factor for CPU speed is called ''IPC'' or INSTRUCTIONS PER CLOCK, the gigahertz is how many cycles the CPU is doing in a dedicated amount of time, so IPC x GIGAHERTZ (actual clock speed of the CPU) technicaly would give you the overall performance of the chip, but this can't be calculated like that since nobody knows the actual IPC of any chips, so we have to rely on benchmarks to really guess wich CPU has the better IPC...then comes the cores and hyperthreading and things like that but those won't change anything all they do is increase the IPC (again the amount of instructions that a chip can process per clock) , but in the end it's all about IPC or INSTRUCTIONS PER CLOCK and GIGAHERTZ...

 

The cache is like the ''storage room'' for all those instructions, it should not affect speed at wich the CPU process the data provided the cache amount is sufficient and fast enough for the CPU in question, and most of the time both AMD and intel are doing a great job at provinding enough cache and fast enough cache for every CPU they produce. Some lines of CPU mostly dedicated to server and workstation applications will have more than required cache amount (Xeon and opteron chips for example) because at some point those CPU's may require larger amount of cache to store data.

 

OP, i think this should be selected as best answer for this thread.

[Guest]

CPU monopoly is all about IPC, should say enough about what makes a cpu fast.

 

Basically this. Instructions per cycle x clock speed = instructions per second. For a single core at least. And that's the main advantage that intel CPUs have over AMD at the moment, even when they are clocked lower and have less cores they can achieve similar performance because the total instructions per second are roughly the same. Of course all of this doesn't factor in the cache size, optimization (8 cores are useless if the program you're using isn't heavily multithreaded), hyperthreading (which can basically increase the IPC even further), etc. If you want to know which CPU is theoretically faster then this could help, but if you want to decide on a CPU then please look up real world benchmarks, look up on the features that they provide, etc.

[Lord Pantaloons]

What makes a CPU fast?

 

Being manufactured by Intel

[samuel]

What makes a CPU fast?

 

Being manufactured by Intel

That's plain wrong. How about Atom vs ARM at the same TDP? 

[Lord Pantaloons]

That's plain wrong. How about Atom vs ARM at the same TDP? 

[flibberdipper]

Red stripes.

 

But really, higher clock speed, more/faster cache, and a better IPC all combined make fast CPUs. Hence why Intel is better than AMD when it comes to performance.

[LegendKillerRG]

What makes a CPU fast is the $$$