Need Help with i7 8700 abnormal turbo clock.

[Nik_96]

Processor:- i7-8700                                                                            hdd:- wd blue 2tb 

Motherboard:- ASRock z370 killer sli/ac                                            ssd:- samsung evo 860 250gb

Ram:- Gskill RIPJAWS V  f4-3000c15s-16gvr  1x16gb                     gpu:- nvidia 1050ti mini

psu:-cooler master 500watts                                                             CPU COOLER:- Coolermaster ma620p

OS:-Windows 10 64bit in ssd

 

Whenever the cpu is under full load it works on 4.3ghz all cores for just 10 seconds after that it just goes down to 3.5ghz or 3.2ghz.

temps were around 70-71 celcius max when 4.3ghz. which instantly drops to 55celcius upon going 3.5-3.2ghz. 

also whenever i make changes to bios the windows takes about 2-3mins to load which normally boots in 10secs.

 

tried some stuff:-  like turning of intel thermal throttling from bios. still no change it does go to 3.5ghz from 4.3 with same trigger temp of 70 celcius.

monitored AUXIN1(VRM temp i think) was around 100 minimum is always 95 or something.

checked cpu socket for bent pins didn't found any.

 

need to narrow it down need help. whether its my psu, motherboard, or cpu....

[SammyV]

Your CPU and/or VRM is hitting its power/thermal limits, which causes the throttling behaviour as per your description. Check and see if you can disable Multi Core Enhancement in the BIOS settings. Many Z370 boards had this option enabled by default.

[Nik_96]

@SammyV couldn't find MCE settings to tweak. but took a turn around.

 

although found some setting for my problem just wanna make sure is it ok to do that.

was messing around in cpu settings in bios and found that long duration power limit and setted it to max from auto.

which stopped the clock rate drop from 4.3ghz to 3.5ghz.

but am pretty sure my motherboard always ran on 4.3ghz all cores under full load whenever i observed it but recently its getting power throttled.

is it my motherboard going bad or something?