Let's read this.
"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. "
OK so your CPUs are more than up to the task but for games it's all about the GPU. Before I share how I compare GPUs you need to shop for the i5 laptops but with better GPUs.
I use notebookcheck in my google search and then the GPU.
So notebookcheck 4000 finds http://www.notebookcheck.net/Intel-HD-Graphics-4000.69168.0.html
A sea of RED for gaming.
OK same search but with the "nvidia nvs 4200" after notebookcheck finds http://www.notebookcheck.net/NVIDIA-NVS-4200M.47343.0.html
Slightly better it seems but a gamer this is not. I'd keep shopping but look for i5 powered machines with better GPUs.
Dell Latitude e6330 :
Intel Core I7 - 3520M
RAM : 8Gb
Graphics card : Intel HD 4000
Dell Latitude e6420 :
Intel Core I7 - 2760QM
RAM : 8Gb
Graphics card : nvidia nvs 4200
Already have both these laptops but I'm gonna sell one so I need to know which is better for gaming