erm... if u wan playing smooth, ur graphic setting can't set too high..
resolution: 1024x768 or below,
Shadow detail: Low
Texture Filtering: Low
World Level of detail: Low
Road and Car reflect detail: Low (ai.. if set to low, car no shine liao)
Other setting: Medium or Low
recommend:
memory: 512MByte or above (now ddr ram price already drop to bottom line, spend around rm180 can get 512mb)
CPU: 2.4G, erm.. u can try o/c to 2.6 or 2.8, this CPU o/c potential not bad, but u need good motherboard and power supply support (p/s: no recommend for person who dont know how to change "BIOS" setting)
Graphic Card: change to 6600GT or above... i use 6800LE (use rivatuner change some hardware setting liao) when resolution is 1024x768: except Shadow Detail and Texture set to medium, other setting i can change to high.
budget need to spend around 600 ~ 1000 (assume u got good mb and power supply)
Wish can help u...