Intel processors hit the hardest due to the recent discovery of Meltdown and Specter bugs. They were supposed to be fixed by a security patch, which, however, was not perfectly prepared.
It turns out that the patch causes problems with restarting the computer. This applies not only to owners of Broadwell or Haswell processors, but also to data centers. The models most affected seem to be the i7 4770K and the i7 6950X. Intel ensures that they are talking to customers and want to fix this problem as soon as possible. Some time ago it was also loud about a significant reduction in processor performance. This has turned out to be untrue and some tests show no change in the results. The only significant difference was noticed in the SYSMark 2014 benchmark.
However, I suspect that there will be many more performance verification tests soon. So far, there was CES and most of the editorial staff were busy with the news displayed there.