CommanderCrap :
The only one that is 2.6 ghz on the intel website is a 920 and that is one of the oldest i7s there is
http://ark.intel.com/products/37147/Intel-Core-i7-920-Processor-8M-Cache-2_66-GHz-4_80-GTs-Intel-QPI
Alright, so he without a question needs a new GPU, can't use the onboard one since he doesn't have a new generation i7.
The CPU itself is still pretty solid as a piece of processing power.
You'll need 4-8 GB of ram, and at minimum an AMD R7 250.