I hate it when salesman say, "What is the computer mainly used for?" who cares, in a very few years, the "biggest and fastest" will no longer run mainstream software.
Bzzzzt.... I'll use bold just to say it loud,
WRONG!
What it is used for will HEAVILY influence its performance in other areas. You get a rig set up for 3D animation and it may not run aces high very well. You focus on a lot of ram, a large HD, instead of a very fast vid card, etc. For a lot of photoshop work you would tailor it differently as well. Fast SATA HDs (maybe RAID for backup as well) and lots of ram, but really not much need for high-end quad-core and the like.
The intended use of a system is very important if you're on a budget.
On the other hand, my P4 650MHz with 300-some MB of RAM (max) and a GeForce 256 (later Ge4400Ti) lasted from 2000 until AH2 came out on games ranging from Half-Life1 to AH2 (which it really couldn't do). That's quite a lifespan of useful service.
Much opposed to Apple's philosophy, computers are NOT throw-away devices (unless they're Dells). They are upgradable and can have their lifespans extended significantly in the majority of cases.
The salesman asks "what will it be used for" because you don't want to sell a Mazda Miata to a construction worker that needs to carpool with 3 other guys and all their tools.
