4790K reaches 100C temperature easily

[FaroukZidane]

CPU temperature is 45C-50C at idle and reaches 90C-100C easily on games like FIFA 17, I haven't tried something more stressful due to danger. I remounted the cooler and reapplied thermal paste but in vain. I know the case is small with limited airflow but I don't believe such reason. Ambient temperature is around 35C but I tried with the air conditioning (ambient temperature 23C) and the problem persists.
Here's a screenshot from RealTemp: http://tinypic.com/r/34ycknt/9

CPU: 4790K
Cooler: Corsair H60
Case: Corsair 380T
RAM: 16GB Corsair
MB: Z97i-PLUS
SSD: Kingston V300 120GB
HDD: 1TB Black
VGA: GTX 970 G1

 

[InvalidError]

Do the return (hot) hose and radiator heat up? If not, you may have a pump issue.

The CPU shouldn't be getting that hot even with the stock HSF.

 

[ko888]

What is your CPU's core voltage when running at full load?

 

[FaroukZidane]

I can't feel any heat when I touch any of that plastic hoses, they are both normal.
CPU's core voltage is 1.299V

 

[ko888]

The problem is with the design of the mounting bracket. On thinner motherboards there is insufficient clamping force applied by the mounting bracket to the cooler pump assembly's copper cold plate against the CPU's integrated heat spreader.

If you currently have this:

and you're seeing the mounting nut protrude, even slightly, above the motherboard's top surface like this:

then you'll get temperatures higher than they should be. You need to add spacers or washers like this:

so that you end up with this:

which should solve your problem.

 

[FaroukZidane]

I've tried many things but no luck. The mounting bracket and screws are like this:

Would the stock cooler perform better in this case? I even want around 70C on games like FIFA 17 until I get another cooler, I'm not saying full load 100%.

 

[ko888]

Did you add the spacer(s) on all four corners like as shown here?