if your budget is 200$ for the cpu , i would sincerely recommend the following :-
Intel Core i5-750 Lynnfield 2.66GHz 8MB L3 Cache LGA 1156 95W Quad-Core Processor - Retail 199.99$
for single video cards , this mobo with one gpu slot :-
GIGABYTE GA-P55M-UD2 LGA 1156 Intel P55 Micro ATX Intel Motherboard - Retail 104.99$
if you need sli/xfire , then this :-
GIGABYTE GA-P55-UD4P LGA 1156 Intel P55 ATX Intel Motherboard - Retail 169.99
this memory is 1333 mhz and has low latency 7-7-7-21 :-
OCZ Platinum 4GB (2 x 2GB) 240-Pin DDR3 SDRAM DDR3 1333 (PC3 10666) Desktop Memory Model OCZ3P1333LV4GK - Retail