gpu clock speed

[Overclock Gamer]

I want to purchase gtx 1060 strix edition and it look like it comes with 4 different clock speed. Please I want to know which one is the clock speed cos I can't differentiate them. These are the clock speed from their website.

Engine Clock

OC Mode - GPU Boost Clock : 1873 MHz , GPU Base Clock : 1645 MHz
Gaming Mode (Default) - GPU Boost Clock : 1847 MHz , GPU Base Clock : 1620 MHz 

[Mick Naughty]

They are all the clock speed. 

[Shakaza]

The base clock is the speed the GPU is guaranteed to run at unless it's thermal throttling. The boost clock is the speed the GPU will run at as long as it runs within the thermal (if it gets too hot while boosting, it will stop, and if it's still too hot with the base clock, it will throttle) and power targets. Not sure why the card has the gaming and OC modes, as the difference between them is marginal at best, but if you keep it in OC mode the base and boost clocks are going to be higher.