CPU overclock suddenly became unstable

[JoJo1070]

Hey whats up guys. Coming at you because I am really confused. In short I swapped out my radiator fans and my overclocked CPU became super unstable. Let us get into Detail. I have an i5 7600k on an Auros Z270 Motherboard and an Corsair H105 240mm Liquid Cooler mounted as an intake on the front. I got the i5 to 5 Ghz on 1.38Volts in the Bios which results in 1.32Volts in Aida64 / Cpu-Z. Mounted to the H105 I have the two standard SP120 Fans as well as one more SP120 because of cosmetics and general room for 3 intake fans in the front. The two SP120s are connected via Y-Cable and run trough a fan controller which only functions as extension and is set to PWM-mode. My temps average at about 60-65 on the Cores peaking at 70 with the CPU-Package beeing about five degrees higher on avg while Aida64 stress testing. Not too bad but the fans sound like a jet engine and it gets really annoying when the CPU goes to 100% while loading or opening programs cause the fans would ramp up to max for a few seconds. I wanted to switch the fans out anyways so I decided to put my Thermaltake Riing12s there which were previously mounted as exhausts. Now begins the fun. My System immediatly got unstable and like ... freakin super unstable. Aida64 would not run for five minutes without freezing my pc. Opening Google Chrome while stressing would also cause a pc crash. During the Stress test the temps were about 10 degrees higher so in the mid 70s on average which is still alright with the fans beeing super quiet. But as I said unforunatly unstable. Highering the Vcore to 1.4V Bios in the Bios / 1.344V Aida64/CPU-Z did not really make a difference. Setting the fans to high rpm would drop down temps a bit but still would not make the systemn stable. On stock everything seems to run just fine with chrome lagging just a little bit while stress testing but i guess thats normal. I haven testet if I can run games while the CPU is overclocked with the Riing fans but even if I would not be satisfied with that if it does not even hold up a few minutes in Aida64. Phew long text ... I hope someone can help me and greets from germany

 

[The Paladin]

3.8 to 5Ghz..quite a jump.. I would suggest dropping it to 4.8Ghz with 1.2v and see how your temps look from there...