New Build - any advice or opinions, please?

I've got around NZ$2000 to spend on a new Gaming PC - Which is about US$1,400.

I've recently blagged a 19" LCD from work, which will do 'til I can upgrade to a 22" or 24" one (using a 17" CRT as a second screen at the moment).

I've got a mouse, keyboard and mic headset that'll also do for now. If I can save some cash elsewhere I'd love to splash out on these too.

The plan is to get the basics sorted, then up-grade to a CrossFire setup when the price of the 4850 cards come down a bit further. Not planning on going larger than 24" monitor in the near future, so something that can handle handle 1920x1200 with good performance and and quality setting would be great.

Not too worried about overclocking (perhaps a bit on the CPU). I would like it to be as quiet as possible.

So far I've come up with the following:

CPU:
Intel Core 2 Quad Q6600, 2.4GHz, LGA775, quad core

CPU Cooler:
HYPER TX INTEL RR-PCH-S9U1-GP

Motherboard:
Not sure whether to go with the cheaper:
Asustek P5Q PRO ATX Intel LGA775 Intel Core2 E Express Gate

Or splash out on this one and try to future proof a bit:
Gigabyte X48-DS4 DDR2 1200 1600M FSB Dual PCI-E 2.0 x16

Memory:
G.SKILL 4GB kit DDR2-800 PC6400 CL4-4-4-12 MEMORY RETAIL F2-6400CL4D-4GBPI

Graphics:
Asustek EAH4850/HTDI/ 512MB ATI Radeon HD 4850 512MB GDDR3 PCI-E
(Will eventually get a second of these, and would probably get a Gigabyte one to match the more expensive motherboard if I chose that option above)

Hard Drive:
Western Digital 640GB SATA 7200rpm hard drive
(Might want another of these in the future too)

Case:
Antec Nine Hundred

PSU:
Seasonic M12 700watt Modular
This is a bit on the pricey side, but I've heard good things about Seasonic. Could I get away with the 500watt version? Any other recommendations for low noise PSUs?

DVD:
LiteOn LH-20A3S SATA 20X Dual Layer DVDRW

OS:
Microsoft Windows Vista Home Premium 64 Bit OEM

Eventually aiming to get a LG L246WH-BN 24" Wide Screen LCD HDMI
or a ViewSonic VX2240W 22" widescreen LCD monitor 2ms 4000:1 depending on budget.

Any help you guys can give me would be very much appreciated. I probably know enough about PC hardware to be dangerous, and I'm by no means confident that the bits I pick will work well together.

I'm limited to buying from New Zealand retailers (oh how I wish Newegg delivered this far).

Thanks for the feedback and the recommendations - that cooler looks great, and the less power I use the better I guess.

p45 board on crossfire is x8/x8 vs the x16/x16 of the x48. that has some effect at 1920x1200 and a large effect higher than that. lower then 1920x1200 it has very little effect. so that might impact your decision.

ram - don't get cl4 ram with high voltage. get 1.8v on your ddr2 800. that is standard and you can always up it if you need to on an overclock. cl4 may look better but if they upped the voltage to get you there (so not better). and i'm sure they are charging you more for it. when really you aren't getting more.

great case and hdd

psu - would recommend corsair, pc power and cooling, antec or OCZ. don't skimp on your power. if you really are going crossfire then get enough. depending on how long you plan to have this you may want to leave enough room for future gpu upgrades.

one option as far as being able to save on the p45 board would be to get the 4850x2 when it comes out. then you wouldn't need to shell out the $$ on the x48 and you would even have better performace vs 2x4850 (or similar). i think release is this month but don't know price.