Can disabling unneeded services really increase the performance of windows XP?

"Way back then, when CPU's and RAM's weren't as advanced as today, with only Single Core CPU's and Single Channel RAM's the answer would have been YES.

With today's advanced CPU/RAM technology they are negligible. Because the CPU's/RAM's are so powerful they, if done right and not overdone**, have no impact on the system performance whatsoever.

**By that I mean if you don't have hundreds of processes and unneeded services running idle. Because even when they are idle and doing nothing the CPU has to check them if they do something or not. Having a couple hundreds of them, I imagine, can have an impact on performance."