cpu - Understanding the differences between different Intel processors

I'm looking at buying a new laptop PC (my old one is failing). I noticed the latest CPU clock speeds are lower than my current one though the CPUs are newer. It used to be that a higher clock speed meant better performance but obviously this is no longer true.

So when I compare CPUs, how do I know what's good or bad? See below a screenshot of 3 CPUs. The one with the worst score is my current CPU.

Thanks,
David.

• Intel Core i7-4510U @ 2.00GHz


• Intel Core i7-2620M @ 2.70GHz


• Intel Core i7-4600U @ 2.10GHz

Answer

Whenever I chose a CPU for a new build I always go here:
https://www.cpubenchmark.net/

I basically look at the scores that the CPUs get and find nitches of where you get a big price drop for similar performance if that makes sense. I usually go for high performance at a good deal but of course if your aim is something like lower power consumption for the performance I am sure there are charts out there for that too.

I like this method because it holds all manufacturers to the same level.

In terms of laptops, I would also look on here for how they score.

CPU speed is more than just the number in front of the GHZ by the way. That is simply how fast the processor is processing at a time but that doesn't take into account how MUCH it is processing at a time. I feel that benchmarking is the easiest way to see the differences without having to look into deep details.