# What's really going on with CPUs?

So I used to think a processors performance was solely based on clock speed and the number of cores.
If this were true then something like the AMD Athlon II X4 760K (Quad Core @ 3.8 GHz) would slightly outperform an Intel Core i5 3570K (Quad Core @ 3.4 GHz) in some tasks, but that isn't the case. So my question is, how can you tell if one processor performs better than another besides looking at the price?

Thanks in advance and keep up the good work Tek Syndicate team!

Looking at benchmarks.

AMD's and Intel's chips are very different in architecture and therefore performance. I'm no expert but from what I hear Intel just has the better factories and architecture to make the cpu's stronger. Their single core performance compared to AMD's is through the roof, which is why AMD has several weaker cores compared to 4 strong cores on Intel's side.

Ok I'm going to try to explain this as elementary as possible.

A modern processor has millions and sometime billions of these things called transistors. they don't do much by themselves but in groups they can solve math problems. Basically transistors can compute stuff.

All these transistors run at a certain speed. This is clock speed Modern parts are in the Ghz range or in other words if you have a 2Ghz processor it can make those transistors do TWO BILLION things a second.

Now logically more Ghz = more performance. this is true. But there's another factor that your missing. Hoe efficient are these transistors at doing things?

(Dealing with single core processors here)

Let's say you have 5X5 and you wanted to solve.

A dumb processor would probably do 5 + 5 + 5 + 5 + 5 = 25

A new smart processor may do things this way- It has transistor built into it that have times tables and it realises that this problem applies

so,....  5 x 5 = 25

What takes less clocks to do? 5x5 not 5+5+5+5+5 because it uses less clock to do so.

this is a much short equation meaning it can use less cycle to compuete it meaning it has more cycle do do other things.

Alot of these little calculations on a huge processor using many more transistors is IPC or instructions per clock- how much stuff can it do in one clock?

So you take the clock speed of a processor and multiply it by its IPC and you get how much stuff exactly it can do a second.

In term of amd vs intel; intel right now seems to have much better IPC while amd has worse IPC and a much higher clock speed to compensate.

Very dumbed version down of how somethings work under the hood.

here's a video on the topic