- Shades

I've just built something almost identical (with a 7600GS graphics card and Maxtor drives.


Everything you've chosen is good stuff so you shouldn't have any problems.
Couple of things to check:-

RAM
The timings on your RAM; Mine is 4-4-4-12 but a lot of vendors try to hide having to describe timings on 5-5-5-15 sticks which are slightly slower.
MOBO
The BIOS auto-defaults on the Asus board were wrong on mine which confused me for days until I set them manually. The mobo you've selected is an SLi board which means the extra graphics slot will remove two PCi slots from your board lay-out. I doubt you will ever need an SLi configuration with that graphics card so you may be able to save something with a non-SLi board. Otherwise it's a good choice.
CPU
The fan that comes with the E6600 is very good and you shouldn't need a 3rd party one to keep your temps down.
It keeps mine idling at 30C and even overclockers are reporting moderate clocks with good temps from this stock fan.
HDD
I don't know much about the Samsung drive but people who have used it give it good reports.
PSU
You haven't mentioned your power supply. Don't make the mistake of dismissing it as unimportant and try to get away with a cheap or generic psu or one that's included with your case. Mine is an Antec Basiq Power 500w ATX 12v and was a very good price, very quiet with a very steady supply. I recommend it and/or not spending less than £40.00 for a 500w psu. There are more expensive ones than that available and for good reason.
OS
What operating system are you going for?
I installed Vista 32bit Home Premium but it has given me some problems I can't get around directly, including not supporting my FFB2 joystick, Norton 2007, and two Belkin Routers.
I don't particularly wish to buy a new stick just to fly CFS1 so I planned a spare partition in advance where I can install XP and make a dual boot system at a later date (coming soon).
Vista 64bit still has loads more compatability issues than even 32bit does. Might be an idea to steer clear for a while.
Especially as M$ are currently saying that SP1 has so many issues to deal with and will be so big that they're not thinking of releasing it until at least Q3 2008 now.
Can't see any problems with XP at the moment although you will probably need to upgrade in a year or so anyway as new Vista games, drivers, and software start to emerge.