Help me buy a new computer

[HisMajestyBOB]

Take a look at Sony's L-series. It's basically a computer in a flat-screen monitor. Plus it's touchscreen!
I don't have any actual experience with it, but it looked cool in the store and wasn't too expensive, like ~$1100.

[viper37]

You definitely don't want the SLI in your suggested Dell - double the cards means double the noise.

Just to add something for Mono:
SLI/Crossfire (AMD) will give you at best 1.5x the speed of a single card.
What you get is better anti-aliasing (better image quality).

And this is useful for some games, not all.  It's worthless in EU3 or Civ V, say.
For FPS or brand new, high profile strategy games, it has it's uses.

I think you'd be better off with an either passive, or slow-spinning air cooled CPU cooler.

Overclocked means that they take the same CPU and fiddle with the settings so that it runs faster - which also means it runs hotter.  With a modern i7 you frankly won't come close to using all of your CPU power anyways, so I'd avoid overclocking.

Liquid cooling is better for overclocking.  You can achieve insane speed with liquid cooling for the CPU and GPU.
Also, don't pay for an overclocked processor, overclock it yourself with the BIOS.

What else can you do?  SSD HD.  Yes it is more money per GB.  But its many times faster, and yes - it's absolutely quiet.  I've read a hundred times its the single most noticeable upgrade you can make to your computer.

A SATA 3 will give Mono good performance, and be relatively quiet.

[Barrister]

When you go Mac, you're limited in the options for graphics cards, which is usually the biggest factor in gaming performance.  Take my Mac Pro, for example - the biggest baddest vid card out there I can get is an Radeon 5870, which has been out for 2+ years already.  If you go iMac The best vid card you can get is a Radeon 6970M - which is a laptop graphics card, albeit a good one.

Thanks for giving me excellent arguments never to buy a mac   These are actually useful because my wife is a huge Apple fan, and she tries her utmost to convince me to go mac 

Way to cherry pick my quote.

[garbon]

When you go Mac, you're limited in the options for graphics cards, which is usually the biggest factor in gaming performance.  Take my Mac Pro, for example - the biggest baddest vid card out there I can get is an Radeon 5870, which has been out for 2+ years already.  If you go iMac The best vid card you can get is a Radeon 6970M - which is a laptop graphics card, albeit a good one.

Thanks for giving me excellent arguments never to buy a mac   These are actually useful because my wife is a huge Apple fan, and she tries her utmost to convince me to go mac 

Way to cherry pick my quote.

I think he just got to the heart of the matter by discarding the fluff.