NEVER GET A DELL OR AN APPLE!!!
those are just about the two worst things you could get...apple is just retarded...and when comparing a dell with something such as an HP, you would kick yourself for getting the dell...
gt an HP, best deal for the money...
also, since you are getting a laptop, be sure to get an intel processor, AMD hasnt quite made it up to par on laptop processor's yet...if you decide for a desktop, go with AMD...
if runescape is the only game you are going to play...if you can even call it a game...then you would be better going to a garage sale and buying a fishtank with a dead shoe inside...because runescape will play on just about anything...
if your a casual gamer but play more hardcore games (WoW, LotRo...any actual MMO's) then you should be looking at at least a 2.0 GHz processor...and AT LEAST 1 GB RAM...try to get an NVIDIA graphics card, basically the higher the number, the better (as with most other hardware components)
if you are a hardcore gamer (i play 8-10 hours a day and still dont really consider myself hardcore...) then you need to step it up to a 2.2 GHz processor...and 2+ GB of RAM...
but seriously...stop playing runescape and get a real game (Age of Conan comes out in march

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