Understanding processor speeds

I've been shopping around lately for a new Laptop. I do tend to stay on the cheap side and with intel... so we shall just leave it at that but my goal is to buy a better Laptop then what I have without spending more then what I did on the first one.

A few years back I bought a msi A6200 with an intel P6200 processor with 2.16ghz dual core. 320gig hard drive with 4gig of ram. I believe I paid about $350 for it.

I've been seeing some that are i3 with 1.9ghz processor. I also saw one that didn't say i3, i5 or i7 but it's speed was 2.13ghz and the store worker said the i3 with 1.9ghz processor was faster. Is my math off or somehow a newer chip has hidden speeds?

They both appeared to be dual core.

Edit: Oops, I posted in the wrong section...can a mod move this thread?

Thanks,