CPU temp testing query

I'm about to put together a build with an i7 7700K (won't be overclocking), Quadro P1000, 2x HDD and 1 x SSD. Cooling will be handled by the Hyper 212X (and a couple of stock case fans).

I'm planning to use the Intel Extreme Tuning Utility to test the CPU temp once the build is done, and was wondering what the recommended time is for running a CPU stress test (it can run for minutes, hours or even days!) using this app?

Any advice gratefully received.