ASUS kicked off its GeForce GTX 660 lineup with a pair of DirectCU II series graphics cards. ASUS' cards combine a non-reference design PCB with its iconic DirectCU II dual-slot cooling solution, which has featured on numerous performance-segment graphics card models. Among the two cards launched are a base model, which sticks to NVIDIA-reference speeds of 980/1033/6008 MHz (core/Boost/memory), and a factory-overclocked TOP variant with 1072/1137/6108 MHz clock speeds. The TOP variant is priced at US $259, while the base model is an estimated $20 cheaper. Based on the 28 nm GK106 silicon, the GPU packs 960 CUDA cores and a 192-bit wide memory interface, holding 2 GB of memory.