Originally posted by King Cobra
The correct abbreviation for "megahertz" is MHz.
Also, other factors to consider:
How much RAM was in each machine?
What apps were open for each?
What OS was on each machine?
What is the bus speed of each machine?
What was the screen res. for each?
In nearly all cases, each factor has to be equivalent (except for the hardware) before comparison. At ideal conditions, the only benefit of having a Cube in the comparison of a 450MHz Cube to a 900MHz iBook is you have a Cube.