Nesticle runs full speed on a 486 processor. Snes and Genesis games run full speed on a pentium 200 (maybe more for the newer fancier emulators).
Visual Boy Advance, I dunno, but it runs full speed on a 650 that I have.
Each step up in mhz over 500 only buys you a tiny handfull of games. You really don't need a expensive, or fast computer for emulation. I keep seeing this scenario over and over again.
PERSON 1: How fast of a computer do I need to run game X?
PERSON 2: Mentions some processor speed that only came out this year.
ME: Hello! That game was running full speed 3 years before that processor you mentioned was even available.
A classic example of this was a thread about a month ago where several people stated that you needed a 500 Mhz processor for Nes games. Man, I have no idea how I was managing to play them full speed on my 40 mhz laptop 4 years ago, or how I still continue to play them on my 100 mhz laptop today.
Buying a 3 ghz computer for mame today is a big waste of money, as the only advantage it has over a 650 is about a dozen games of questionable quality that are either EXACTLY like 100 other games in Mame (the fighting and sports games), or require funky controls that you probably don't have anyway (Cruisin, Stun Runner, Prop Cycle, Area 51, etc).