In this web article "Working Around The Intel Core i7 5775C Broadwell Stability Issue On Linux", the author indicates that he and others have seen stability problems when running Linux on Broadwell-microarchitecture i7 processors. I am having similar issues with a i7-5700HQ. In both cases, a workaround related to SpeedStep or similar power/performance throttling was discovered.
Is it possible that Intel has released a microarchitecture which does not run Linux (reliably) without disabling frequency scaling -- or is it more likely that these issues are due to manufacturing defects in the particular hardware units under test?
Update: The problems were fixed for me with the BIOS/microcode update desribed here. As noted there, problems were discovered while running Windows as well. I don't have enough information about the update to know if this was Intel's fault or something specific to the manufacturer of my laptop.