Design and Features
The Zotac GeForce GTX 660 2GB is as compact as its Ti cousin, measuring 173x100x38 millimeters. It’s actually rather hard to tell them from each other.
The new card is equipped with DVI-I and DVI-D (dual-link) outputs as well as with HDMI and DisplayPort. There’s also a vent grid in the mounting bracket to exhaust the hot air out of the system case.
The GeForce GTX 660 has only one MIO connector (for building SLI configurations) and one 6-pin power connector.
Thus, you can only join two such cards in a SLI setup. The peak power consumption of the GeForce GTX 660 is specified to be 140 watts while its typical 3D consumption is 115 watts. A 450-watt or higher PSU is recommended for a system with this graphics card (the same as for the Ti version).
The GPU is placed in the center of the small PCB. It’s surrounded by memory chips.
In the back part of the PCB, below the small aluminum heatsink with thermal pad, there are four phases of the GPU voltage regulator:
One phase is placed between the GPU and the video connectors. It is responsible for the memory chips and has no cooling.
The card’s GK106 revision A1 processor was manufactured in Taiwan on the 31st week of 2012 (late July or early August).
It is 24.8% smaller than the GK104, but the exact transistor count is not yet disclosed. The base GPU frequency in 3D mode is 993 MHz (1059 MHz in the boost mode), which is 78 MHz higher than the base frequency of the GeForce GTX 660 Ti. The Zotac is pre-overclocked by a mere 13 MHz compared to the reference GTX 660. The GPU voltage is 1.175 volts. In 2D mode the GPU frequency is dropped to 324 MHz at a voltage of 0.987 volts.
Unlike all of the Kepler-based graphics cards we've tested previously (with the exception of a dual-processor GeForce GTX 690), the Zotac GeForce GTX 660 carries memory chips from Samsung rather than Hynix.
Labeled K4G20325FD-FC03, the chips have a voltage of 1.35 volts and a rated clock rate of 6000 MHz. The card indeed clocks them at 6000 MHz. Coupled with the 192-bit bus, the GeForce GTX 660 has a peak memory bandwidth of 144.2 GB/s, like its Ti cousin.
The latest GPU-Z is already aware of the existence of the GeForce GTX 660 and reports its specs correctly:
There are still no tools available that could read the BIOS of Nvidia's GeForce GTX 6xx series cards, so let's move on to examine the cooler.