Can you put an i5 4590 on an Asus P7P55D Pro motherboard?

Solution
Nope, i5 4590 requires a socket 1150 mobo, that is socket 1156 I believe. But you can't unfortunately, no.

Edit - yep, I was right. P55 is Socket 1156. The best processor you can get for that is an i7-870, launched in 2009.


The number difference (mostly) matches up with the generation.

3 digits like the i5 750 & i7 860 were the first generation of Intel's "core" processors.
then you have 3 further generations:
Sandybridge are ix 2xxx processors
Ivy bridge are (mostly) ix 3xxx processors
and then the current Haswell are (mostly) ix 4xxx processors.

So you can think of the digit before the last 3 digits as the generation, with higher being newer. It doesn't quite work out because the "extreme" CPUs (like the i7-3960X) are usually given one higher first digit. But for most of the consumer processors (all i3s, i5s and most i7s) the above formula works.