"Our tests demonstrate fairly little difference between a $225 LGA 1155 Core i5-2500K and a $1000 LGA 2011 Core i7-3960X, even when three-way graphics card configurations are involved. It turns out that memory bandwidth and PCIe throughput don't hold back the performance of existing Sandy Bridge-based machines. "
http://www.tomshardware.com/reviews/gaming-cpu-review-overclock,3106-4.html
The change of OS and drivers mean it may take awhile to approach or pass up the old PC. But given the hardware changes alone I would not expect higher numbers in the benchmarks you noted.
Bob
Built computer with what I thought were a better motherboard, CPU, & RAM and upgraded Windows 7 to 8.1. My new computer boots fast, runs fine and seemed ok until I benchmarked its performance with 3DMark - and found out I was getting significantly less FPS and 3DMark scores than my old setup.
Old Computer
-------------------
Motherboard - Alienware 046MHW, Intel P67, 1155
CPU - Intel i7-2600, 3.4GHz
GPU - GeForce GTX 760
OS HD - 250GB Samsung 840 EVO SSD
RAM - 16GB Hyundai Electronics 1333MHz
PSU - 875 Watt Dell Power Supply
OS - Windows 7 Home Premium
New Computer
--------------------
Motherboard - Gigabyte GA-Z87-DS3H, ATX 1150
CPU - Intel i7-4770K, 3.5GHz
GPU - GeForce GTX 760
OS HD - 250GB Samsung 840 EVO SSD
RAM - 16GB Corsair Vengeance Pro 1600MHz
PSU - 850 Watt XFX P1-850B-BFX
OS - Windows 8.1
I got virtually no improvement in FPS or score when running Fire Strike Benchmark in 3D Mark when I made the following adjustments:
1. Set NVIDIA Control Panel to max performance instead of quality.
2. Changed Windows settings to best performance rather than appearance.
3. Minimized the number of start-up programs.
4. Optimized SSD performance with Samsung Magician software.
Any help or advice in trying to figure what's wrong with my new configuration and/or components would be appreciated. Thank you.

Chowhound
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