According to a report by Hardware Luxx, heat issues are the reason why Intel is removing FIVR from its next two CPU generations. If the report is accurate, the 14nm Skylake and Kaby Lake series will not have an integrated voltage regulator, but the source claims FIVR will be back with the introduction of Ice Lake:
However, "Ice Lake" as the generation after next is codenamed, will then one again use a FIVR. A source not only provided us with the news, but also gave a reason: the thermal design power of the overall CPU package was too high. This seems to have had a negative impact on the overall system, Intel has to save the extra heat elsewhere.Intel's processor roadmap has become somewhat of a mystery recently as the rumor mill indicates Intel has delayed its 10nm Cannonlake. So instead of Cannonlake, the 14nm Skylake will be succeeded by 14nm Kaby Lake - a break from the firm's tick-tock release cycle. Ice Lake is a codename we haven't heard before, the report provides little details about what Ice Lake is so we can't say for sure how Ice Lake fits into Intel's CPU roadmap. The Hardware Luxx report makes no mention of Cannonlake so perhaps Ice Lake arrives before Cannonlake or maybe Cannonlake has been cancelled completely.