I have a i7 2600K overclocked to 4.6GHz, and my games are getting more laggy as this chip ages. I can take it up to 4.9-5GHz, I usually use Offset Mode for voltage and left most of the other settings (e.g., load-line calibration) to their default. Right now, with a 4.6GHz overclock it usually stays between 1.3-1.4V, and at 4.9GHz before I observed upwards of 1.5V. The cooler I am using is a Hyper 212, and haven't observed the temperatures getting too high (around 70-80C).
Should I be able to overclock more? Is it worth it, will it make much of a difference? The main things I'm worried about is wear on the CPU, and wear on the Power Supply.
Specs:
CPU: Intel Core i7‑2600K
MOBO: Asus P8P67 Deluxe
RAM: HyperX 16GB DDR3 1600
GPU: Sapphire Tri-X R9 290
PSU: Corsair GS600
CPU COOLER: Hyper 212 LED