Cougar is the hotest thing from TM right now..
Asus or Abit Mobo (nice OCing ability)
AMD or Intel - the choice is yours.. u can get a XP2500 for close to nothing and clock it past 2ghz if u know what ur doing or u can get a P4 for a little more - all depends on ur budget
1Gb RAM isn't considerable these days with the price of RAM..
i'd hit Ebay for the GC i got my ATi 9700pro 128 from there for a cheap as chips £160 :)
as for 256mb RAM graphics cards - with the way that textrure compression works i doubt u'll b using over 32Mb of Texture RAM @ 1280 with LO:MAC, but i seems that Graphics Card Manufacturers want Joe Public to have the same RAM on their gaming cards as on a professional rig.. :roll: