Umm I can see you're totally getting ready for cyrsis . Would recommend you go with the 640MB version of the gfx card. Also if possible try to get x2 74gig raptors 10,000rpm drives in RAID 0 that always makes things faster. Thats a decent motherboard for the price but you could always go to tiger and check a few they have. Good build overall.
the 640mb version would only help in 1920x1200 anything less and there is really no point. Raptors offer minimal speed gains over the standard 7200RPM hard drives and in most cases are a waste of money.
raptors still are nice though, i had one before. but yes as you said a fast 7200 drive is still in the same league with raided 7200s often coming pretty damn close. RAID10 FTW betch...
If you gonna buy in aug, try then again. The prices will drop and you can buy things much better. So wait till end of july or begining of august.