Unlike its "Ti" cousin, the GeForce GTX 660 is not based on the GK104 silicon, from which several other GPUs, such as the GTX 670, GTX 680, and the dual-GPU GTX 690 are derived. The GTX 660 is, instead, based on the new GK106 silicon, which makes its desktop debut today. The GK106 is a physical downscale of GK104, which retains all its features, including component hierarchy, but has fewer numbers of them. The GK106 silicon is smaller, with a die-area of 221 mm² and transistor count of 2.54 billion (compared to 294 mm² and 3.54 billion of the GK104). The GK106 is built on the same 28 nanometer silicon fabrication process. A smaller chip results in reduced power draw. A case in point is that the GeForce GTX 660 needs power from just one 6-pin PCIe power connector; the GTX 660 Ti needs two of them.