quick question

What engine is more complex? Source or Unreal Engine 2.0?
I lag more on L4D than Killing Floor and KF has much better graphics imo.
Answer #1
i think Source Engine looks better and has more features. you should be comparing it with Unreal Engine 3 since 2 is a lot older.
what are you PC specs?
http://en.wikipedia.org/wiki/Source_engine
http://en.wikipedia.org/wiki/Unreal_Engine