[CORed]

As others have said, memory and video cards are upgrades you can do yourself pretty easily and probably save money by buying from somebody other than dell. If you want more hard drive space than the minimum, and can get the space significantly cheaper from a third party vendor, it would probably be easiest to add a second hard drive. If you replace the original, you will have to reinstall OS and other software on the new one: Not real difficult, but fairly time consuming. Dell is good about providing CD's for all installed software and drivers, unlike some other manufacturers.

One downside to adding hardware form other sources is if you have problems and need warranty repairs. Dell may claim add-on component is at fault and the manufacurer of the add-on claim that Dell's mother board is the problem. If you buy everything from Dell, there is no question whose responsibilibty it is. However, unless you buy and extended warranty, most likely nothing will fail befor the 1 year runs out, so if there is a significant price advantage, I wouldn't let the possible warranty issues deter me from buying the add-on. On my Dell, the first (and so far only, knock on wood) hardware failure (dead power supply) happened about 1 month after the warranty ran out.