8700k FPU test downclocking?

[KFC]

This is quite weird or is it normal? My 8700k running stock with no overclock all cores down clock to 4.1GHz during the FPU test alone. CPU test alone will run at the full 4.3GHz. Why is the FPU dropping all cores down to 4.1GHz and is it normal?  

[Fiery]

The FPU subtest of the AIDA64 System Stability Test is a more demanding task than the CPU subtest.  While the FPU subtest is running, your processor is hitting its pre-programmed power limits, and has to run at a lower clock speed in order to obey the power limits.

[KFC]

Ah so that is what it is. Thank you so much for answering that! 

[Snakeyes]

Thank you Fiery.I was running into the same problem when testing my i7 8700K. Please forgive my ignorance, but what exactly are the "preprogrammed power limits" that is, can they be changed or are they locked into the CPU or is there a bios adjustmen that can increase their limits?

[Fiery]

On ‎2018‎. ‎04‎. ‎24‎. at 10:12 PM, Snakeyes said:

Thank you Fiery.I was running into the same problem when testing my i7 8700K. Please forgive my ignorance, but what exactly are the "preprogrammed power limits" that is, can they be changed or are they locked into the CPU or is there a bios adjustmen that can increase their limits?

Those limits are the properties of each CPU SKU.  For your CPU it's 95 Watts, but there can be different values for short-term and long-term Turbo Boost.  The power limits can be re-configured in most retail motherboard BIOSes.