Built upon the same GK104 GPU used in the 690/680 and 670 models, the GTX660 Ti retains the Kepler moniker and deservedly so because the GTX660 Ti utilises the same amount of CUDA cores as the GTX670. Coupled with 2GB of GDDR5 you could be forgiven for thinking there was very little to choose from between the GTX660 Ti and its bigger brother, the GTX670 and to be honest you would be right in thinking that - even the default reference clock speeds are the same.

The difference between the two comes down to memory bandwidth. The GTX660 Ti has a its memory interface reduced 192-bit from 256bit on the GTX670. All is not lost though because the GTX660 Ti's memory controller supports mixed density memory module operation allowing NVIDIA to cram a 2GB frame buffer onto the board. This will inevitably lower the performance below that of the GTX670 howeverm the GTX670 is not the GTX660Ti's adversary. That claim is held by the HD7870.

The reference clock speed of the GTX660Ti is 915MHz which equates to around 980MHz 'Boost' clock speed, 20MHz short of AMD's 1GHZ Edition HD7870. The GTX660Ti's memory is clocked at reference to 6008MHz data rate compared with the HD7870's 1200MHz with the ZOTAC's memory weighing in at 6608MHz. Power draw of the GTX660Ti is however a good 40W less than the HD7870. The figures don't lie though and on paper at least, the HD7870 appears to be the faster card. How this will transpire in real world use we will see later in the review.

there are however a few key differences between a reference GTX660Ti and the AMP! Edition, namely the enhanced core clockspeed which see a 6% boost. This boost, ZOTAC claim, will result in an average 13% increase in performance.

ZOTAC GTX660 Ti AMP! Extreme Specification