Nvidia is rumoured to shortly launch a new Maxwell GM204 GPU which will power at least four new GeForce GTX graphics cards.
Reports suggest the GTX 880 will launch in Q3 2014, with the second wave of cards set to launch next year.
It's possible that the GM204 powered cards will not fall under Nvidia's usual GTX branding but will receive a tweak instead, whether it's GTX+ or a different name.
There's also another theory that the GTX 880 could be relaunched as GTX 970.
Other rumours state the GM204 chip would feature between 15 and 20 SMs (1920-2560 CUDAs) and use a 16nm node.