CPU Scaling and Performance
Using the Windows Task Manager we can see that Deus Ex: Human Revolution heavily utilizes two cores of our Phenom II X6 1100T processor while the other four are working at around 20-40% capacity. Please ignore the 6% CPU usage indicator as it dropped down from around 50% once I hit ALT+TAB out of the game to grab that screenshot.
The Resource Monitor was used keep an eye on the average CPU usage of Deus Ex: Human Revolution and here it is reporting an average of 45.5% across the six cores. This is going to cause some real issues for dual-core processors.
Overclocking your Core i7 processor is not going to help deliver more performance in Deus Ex: Human Revolution with a single GeForce GTX 580 card. With the Core i7 clocked at 2.0GHz the GTX 580 averaged 73fps. Meanwhile a 90% increase in clock speed for the Core i7 allowed for just a 5% increase in frame rates.
Processors that only support 2-threads do not appear fit to play Deus Ex: Human Revolution as our Phenom II X2 560 delivered just 44fps. This meant that the Phenom II X2 560 is about 43% slower than a similarly clocked Phenom II X4 processor.
The Athlon II processors are also pretty useless without their L3 cache as the quad-core Athlon II X4 645 averaged just 51fps. The new AMD A6-Series and A8-Series processors did quite well delivering 67fps and 71fps respectively.
The older Core i5-750 and Core i7-920 processors performed well with 72 and 73fps a piece. The Phenom II X4 980 was surprisingly fast with an average frame rate of 79fps making it only slightly slower than the Core i5-2500K and Core i7-2600K processors.