What's the best gaming computer?

All you GAMERS, please help me get a best gaming computer?
hey everyone, I am planning to buy a computer,initially I thought to buy a laptop but since they are not upgradeable, I shifted to desktops.(Are there any top gaming laptops?). Now I want to buy...

a pc that can play all the latest games out there(I.e positive for any system requirements required for the game). I have given my personal preferences below.
PROCESSOR- I want something above 3 ghz but core duo has something like 2.4 ghz and pentium 4 had 2.6 ghz.
so which which processor?is there any intel duo core above 3 ghz processor
RAM-2 gb or more
GRAPHICS CARD- nvidia series(which one can play the latest games with best graphics)
MONITOR-21 inch
WIFI- my college provides free wifi access and I download lots of stuff from net.As it is not posssible to take the desktop(which I preferred just because of gaming) do you think I should buy some iphone or any other wifi enabled mobile phone to download content and then take to home and transfer.So please help me by suggesting the best

A custom-built computer will most likely work out cheaper for you, and you can be sure of the components in it because you chose them. A few notes to ponder:

Processor: With dual core processors, they are almost essentially two processors in one. So although the clock speed is 2.4GHz, there's two dies/cores working at that speed each, so theoretically you double that and the single-core (normal type of processor) equivalent clock speed is 4.8GHz. Reality is that its not quite 4.8GHz, but its not far off it - would be no less than 4.6GHz. And if you're going with an Intel dual core processor, only get a Core 2 Duo, and not just a Core Duo - Core 2 Duo's are faster, more efficient, and 64-bit compatible whereas Core Duo's aren't. You are going to want to have a 64-bit compatible computer - games will take huge advantage of this in the future, many already do. A lot of gamers like AMD processors instead of Intel - any AMD dual-core processor will be 64-bit anyway.

Ram: Depending on what Operating System you intend on running, 2Gb is probably a minimum for a gaming computer. Make sure that the maximum Ram limit of your computer is no less than 8Gb, preferably 16Gb.

Graphics Card: If you're going to use Windows Vista, make sure you get a good one that has compatible drivers, not all graphics cards do at the moment, even the newest ones.

Hard Drives: Make sure they're SATA, and SATA II at that. Don't bother with Nand Flash drives yet, they are really expensive and don't offer much room at the moment. With SATA II drives your computer will be even faster, especially if its 64-bit throughout.

And stay away from Dell if you can - desktops aren't so bad as the laptops, but just remember, they're cheap for a reason.

There are at least two manufacturers that specialize in gaming hardware:

http://www.alienware.com/
http://www.voodoopc.com/

You may also want to check out if Dell has something you would like in their XPS line...

Alienware is good, but expensive. You'd be better off (if you know someone who'll do it for free) building one, you'll save a lot of money...

pcspecialist.co.uk

Any of you ever heard of pricewatch.com? Is it legit?