"go to this link http://www.majorgeeks.com/
and down load cpufsb in the processor section in the side bar of the website.its $13 but you can try it out for 30 days and their is a free version to but it has no support its called SOFTFSB.on the same website"
I found that using "google", it's a really cool search engine that myself along with others love to use
but anyways, my basic theory is that.. I don't think they can be because like D4RK said, they have it on lockdown, but either way dell's are made to run, like web browsers, word processors and maybe 2d games like.. free cell or solitare... anyways, yea of course you can upgrade the pc's hardware items, but either way your stuck with a mobo and ram that is good as it won't die on you, but sucks on benchmarks, stats, etc... If you find a way to overclock, give it a shot of course, but be veryyyyy careful
-That's my 2 cents