Design and Functionality
ASUS cards can be easily identified by the unique DirectCU II cooler which covers the entire face side of the PCB. We are really fond of this austere design style:
The corrugated casing of the cooler with red inserts matches perfectly the matte blades of the two fans. The heat pipes go beyond the top edge of the PCB but don’t make the product look bulky, even though the ASUS GeForce GTX 660 DirectCU II OC is considerably larger than the reference card from Nvidia. Its dimensions are 259x132x38 millimeters.
We have a standard selection of video interfaces here: DVI-I and DVI-D (dual-link), HDMI and DisplayPort. There’s a vent grid in the mounting bracket to exhaust the hot air from the cooler.
One MIO connector for building 2-way SLI configurations and one 6-pin power connector can be found in their conventional locations:
ASUS specifies the peak power consumption of this card at 150 watts, which is 10 watts higher than Nvidia’s specs. But the recommended PSU rating hasn’t changed. This card is supposed to be used with a 450-watt or better PSU.
Like in its top-end products, ASUS makes the card overclocker-friendly by using a custom PCB with an enhanced power system.
There are six, two and one power phases for the GPU, memory and PLL, respectively.
Combined with Super Alloy Power technology which means the use of high-quality and durable components, ASUS’s exclusive DIGI+ power system ensures 30% lower EMI, 15% higher energy efficiency and 2.5 times longer service life compared to the reference card. It is based on an ASP1212 controller.
So we can expect this graphics card to have high overclocking potential and have a long service life at increased clock rates.
The GPU of our ASUS GeForce GTX 660 DirectCU II OC was manufactured in Taiwan on the 32nd week of 2012 (in early August). It is a revision A1 chip.
Incorporating 2540 million transistors, the GPU has a standard GeForce GTX 660 configuration with 960 unified shader processors, 80 texture-mapping units, and 24 raster operators. It is pre-overclocked by 4% to 1020 MHz (1085 MHz in boost mode). The 2D frequency is 324 MHz.
The ASUS GeForce GTX 660 DirectCU II OC is equipped with eight FCBGA-packaged GDDR5 chips with a total capacity of 2 gigabytes. Manufactured by Samsung Semiconductor, the chips are marked K4G20325FD-FC03:
The chips are rated for 6000 MHz and are indeed clocked at that frequency. Coupled with a 192-bit bus, the peak memory bandwidth is 144.2 GB/s, just like on the reference GeForce GTX 660.
Here is a summary of the ASUS GeForce GTX 660 DirectCU II OC specs: