So I've been testing out some overclocking, and that best I can get is +125mhz on the core clock and +550mhz on the memory clock. http://www.newegg.com/Product/Product.aspx?Item=N82E16814130933&cm_re=EVGA_GTX_760-_-14-130-933-_-Product is the model of my gpu. My temps never go over 67c, but is it actually a safe overclock?