I used to work in the computer department of a well-known electronics retailer a couple of years back. Thing is they taught me some things on pc's, and within the last year i have come to know that some of the information they gave me is not entirely accurate. For instance, they told me that the processor speed and the amount of memory on your pc is what determines the speed of your pc. But i know some that say the hard drive space is what determines the speed of your pc. I guess my question is, What really determines how fast a pc runs?