The official Comanche 4 demo contains one single-player mission. The "Eagle's Talon" mission takes place on an island in the middle of a hostile invasion. During the mission you must provide enough air support to allow friendly forces to land on the beach. Then you move on to destroying a massive cargo ship. Finally, you escort an operative who has just planted explosives to an extraction point. Of course, all of this takes place under a hail of enemy missiles and gunfire from boats, helicopters and ground troops.
This is an excellent benchmark for CPU and Memory.