Please state your general region so we can shop in the same currency. I'm seeing different prices so I'm not sure where you are shopping.
The only decent Intel branded mobo's were the x38 and x48. Even then, Asus and DFI iced their cake like no one's business.
Looks like a nice build there. I'm a fan for Evga myself and would buy their P55 and GTX465 before anyone else's but it's all about preference, I guess. I'm not one to suggest mATX boards, but since the board you've chosen is, I offer this as an option: Evga P55 SLI Micro
. You can go cheaper with a full ATX (7 slot)
non-SLI and even cheaper with a mATX P55 with slower RAM support
. Regardless of price, the Evga boards have just as much quality as their high end.
Corsair makes a nice PSU and the wattage chosen is fine.
If you're going for a 500GB, choose the ST3500418AS (SeaGate Barracuda 7200.12 500GB/16MB) I built several computers for myself and others using this drive and it's a real performer! Single 500GB platter.
The i7 860 is a fine processor.
The monitor? Like all AlienWare products, you're over-paying for something that can easily be substituted. Personally, I like HP Monitors. The picture is pretty crisp and the build quality is excellent. On top of that, they are reasonably priced. HP S2331 23"
OCZ has become disappointing lately, so I'm reluctant to suggest their products to other people. I can still deal with it because I've tweaked their products before. Corsair makes very nice RAM, anyways.
H70, not really necessary unless you're overclocking. But at how expensive air coolers are getting...You might as well.
The HAF 912. Never seen one close. I've seen the 932 and 922, and both were impressive. Plus I've always loved CM cases. There's no way to lose on this choice.
DVD drive looks alright, no problems there. Just make sure it's SATA