Fps drops, stutter , lag , fresh build

[alec.op.au]

Specs:
CPU: i5 6600k
Motherboard: Gigabyte Z170-HD3
GPU: GTX 1070
Memory: 16 GB Corsair Vengeance
Power Supply: FSP Hexa+ 550 Watt
Storage: SSD Samsung 850 PRO
Cooling: Cooler Master Masterair MA610P
Mouse: Steelseries Rival 600
Headset: Steelseries Siberia Elite
Keyboard: Steelseries Apex 350
Display: VG248QE 144hz
OS: Windows 10 Home Edition
Connection: Ethernet 10mb/sec . 40ping/ 0% packet loss or choke

Issue: While most noticeable in cs:go but happens in other games too. Fps drop from 400 to 100 every second causing about half a second screen freeze.
*Countless fresh windows re-installs, secure erase SSD.
*Power options high performance.
*Nvidia latest drivers and settings optimized for performance (also tried with previous driver versions)
*Boot options forced to 4 processors
*Disabled Game DVR, Cortana,etc.
*Temperatures are fine, cpu max temp while gaming around 70 C Max and 50-60 for GPU
*Overclocked CPU 4.2 GHZ , stutter.
*Bios Default settings no overclock at all, stutter remains.
*Disabled C-states and any other bios power saving feature, stutter.
*High Precision timer off/on no difference, xmp profile 1 or disabled , no difference.
*Running CPU at only 3.9ghz the stutter problem persist.
*Switching mouse,keyboard,headset from 3.0 usb ports to 2.0 usb ports made no difference
*Windows 10 Defender Security disabled, no changes.
*Disable Full screen optimization checked

Really frustrating , first time posting here as I really need help and ran out of ideas.

Please do not reply with answers to fix this that involve deep registry changes, game booster and other software.

 

[t99]

What happens if you cap the fps at 100 does it dip lower? If not then what about at 144


Try this as it will help spot irregularities.. If you aren't using monitoring software then download msi afterburner and run it while you play some games. This is safe software and one of the most common software to monitor things like gpu and cpu usage, power usage, frames, all of it, but it shows on a graph over a long period of time so you can see what else happens when the dips takes place.

You don't need this if you have monitoring software already, use whatever you have, but you should see some type of pattern when your dips happen. If you don't I wouldn't really call this other software, it's very basic and honestly great for any gaming pc to have.