In addition to already released GeForce GTX 750 Ti, Gigabyte decided that their factory-overclocked model was far from what it can achieve.
For that reason Gigabyte introduces even faster GTX 750 Ti with a GPU clock up to 1215 MHz (base) and 1294 MHz (boost). This is simply what I told you about the overclocking GM107 potential even before Maxwell was released. Back then I mentioned that manufacturers will come up with 1.3 GHz cards, and this is exactly what is happening here.
Gigabyte GTX 750 Ti OC (GV-N75TWFOC-2GI) packs 640 CUDA cores, 2GB GDDR5 memory clocked at 5400 MHz, dual-fan WindForce 2X cooling solution and a brand new box art (I was getting bored with Gigabyte boxes design!).
TechPowerUp has no further information about the release date or the price.