im building a new box primaly for gaming.
im looking at getting -  
 
-Asus P5K-E/WIFI-AP mobo
-HD 4870 512mb
-Intel core2duo E8400 3.0ghz 6MB L2 Cache LGA 775 65W
-4g corsair memory 6400 C5
-500g seagate hard disk sata II
-Cool Master RC690 case
-logitech G15 key.b
 
im not sure what PSU to get but i was thinking of getting a Corsair HX-620W. will this be enough for for the GPU and a little overclocking??
 
getting a 22" when i get some more money  

You should get better components if you have a $1500 budget. Or are you trying to spend as little as possible?

get 4gb of ram - 2gb will soon be too little

the little money the better. though i dont want to buy the top of the range stuff because i find it to overpriced and not worth it.