Intel Performance Mode (and problems)?

Well, lately I made a new gaming computer together and wanted to run a stress test and realized that I had 90 ° C (maybe wrong) (I ended the stress test before then quickly). On the second try, after seemingly disabling the performance mode with this Intel TBMT program (I thought), the CPU was running slowly but constantly hot. CPU Z also showed me 4.1 Ghz instead of 3.5 and shortly thereafter gabsn still image. (had to start forcer)

Specs: 9900X, Asus X299-e Gaming, GTX 275 (later Titan X (P)), 16GB RAM, Celsius 36 Waku.

Strangely enough, I had the freezen with the FPS testing with Minecraft.

Does it bring here what to disable the performance mode and if so how?
Does the freeze have something to do with the performance mode or is this the Gafikkarte (GTX 275)

At 90 degrees, a CPU makes an emergency shutdown. By the way, the graphic as well.

You have a cooling problem.

So much for water cooling.

Keep the CPU and GPU working within the specs and check if the CPU cooler is flat. Also always use as little thermal compound as possible. Very thin layer. Not much help with thermal grease.

To test the graphic "Furmark" use. Displays the frames and GPU temperature.

CPU… "Coretemp" plus "Prime 95"

Well, I've checked everything now, at 80 ° C comes anyway, but cools down when I turn off the stress test in less than two seconds to 30 ° C down.

80 degrees is still, especially since the thing is supposedly running with more than 4 Ghz, what a CPU eigendlich only endures for a short time.