Gigabyte changes the PCB design of the GTX Titan without changing it.
Some manufacturers are finding ways to modify the GTX Titan while still abiding to Nvidia's terms for card design. Gigabyte is not the first to release an accessory for the GTX Titan, but it is the first to alter the PCB design (sort of). It is called the Gigabyte G-Power, as Chinese site Expreview reports.
The standard PCB design of the GTX Titan is good, but it can be done better. To improve overclocking, Gigabyte has created a secondary PCB which packs a 6+1 phase VRM design. It is intended to be used in conjunction with the GTX Titan by soldering it to a number of points on the GTX Titan PCB. The idea has been seen before in EVGA's EPower and Asus' Matrix PWM.
The device needs an 8-pin EPS connector as well as a 24-pin ATX connector, which might make it a bit unpractical for practical use.
As a result of the added VRMs, the GTX Titan should suffer from much less vdroop during extreme overclocking, which should, in theory, make higher overclocks possible, or even stable.
It remains unclear on how Gigabyte intends to market the device, if at all, but hopefully we'll know soon enough!