I have two EVGA GTX 780 SC with the ACX coolers. I am using MSI afterburner to overclock and am monitoring with GPU-Z. With no overclock, my first GPU core clock is 1071 MHz, and my second is at 1100 MHz. Now, when I apply an overclock under +12 MHz, nothing changes. Nothing. The core clock on both card remains the same. When I apply an overclock of +13MHz to +25MHz it goes up to 1084MHz on the first card. The second card behaves differently, not increasing until I apply an OC of +14MHz. It goes up to 1123MHZ at this point, and doesn't increase again until I increase the OC to +27MHz, at which point it goes up to 1136MHz. Keep in mind the cards are linked in MSI afterburner. These incremental increases continue to what I presume is as far as I can overclock. The problem with this is I can't overclock in increments like normal, I have to find these "sweet spots". The same problem arises with EVGA precision. Is this normal?