I have recently upgraded to a new i7 4790k, and it works fine through the boot and everything. The one issue is that the CPU temp reads out to be 128 degrees (Celsius if anybody wonders). This is causing it to be throttled by up to 75% so far. I'm using an Antec Kuhler 920, and I know it's not the bad part, as it has treated my i5 3570k OC'ed to 4.6 very well.
What I tried (These didn't work, obviously):
Playing games or stressing it won't change anything, it either just stays the same, or it throttles even more.
Other things that might help:
I'm out of ideas to fix this, I looked all around for this issue under an idle, but everybody else just gets 30-60 on idle speeds. I really hope that I can fix this with a simple thing.
In regards to your issue please check the document that was recently posted in the community.
It is a guideline in how to troubleshoot this kind of issue: https://communities.intel.com/docs/DOC-23517