CPU and GPU usage load drops while gaming

[wasilev.8v]

About a week ago I upgraded my GPU and installed an extra SSD in my machine. Since then, I'm experiencing consistent CPU and GPU usage drops while gaming. I did install a brand new Windows 10 Pro x64 and there are barely any other programs on my PC, except Steam and the games I've installed. For the tests I did, I didn't run anything in the background. Usually I have Discord and Google Chrome open for most of the time.
Problem is, depending on the game, I experience frequent and severe CPU and GPU usage drops, lasting for about 1-4 seconds, resulting in FPS drops at these times.

System specs:
- CPU: AMD FX8350 Black Edition 8 Core Processor
- GPU: Zotac GeForce GTX 1070TI 8GB Mini 8GB GDDR5 256 bit
- Motherboard: Asrock 970 PRO3 R2.0
- RAM: Corsair Vengeance Pro DDR3 2400 C11 2x8GB
- Drives: 1) WD WD10EURX 1TB (rather old HDD); 2) Samsung 970 Pro NVMe PCIe M.2 512GB (in a PCIe 2.0 socket using an adapter)
- OS: Windows 10 Pro 64-bit

Here are some in-game images of the CPU and GPU usage drops:

ATLAS with maxed out settings:

ATLAS with minimal settings (Discord and Google Chrome running in the background):

PLAYERUNKNOWN BATTLEGROUNDS with maxed out settings:

PLAYERUNKNOWN BATTLEGROUNDS with minimal settings (no problems here):

Dark Souls III with maxed out settings (no problems here):

Troubleshooting so far:
- Re-installed graphic drivers, several times
- Set the power plan to "High performance" to avoid defrag
- Monitored CPU and GPU temperatures - CPU averages to 55C° and GPU to 65C°
- Turned Off some Windows cloud service for peer-to-peer downloads

 

[Supahos]

Can you try undervolting your CPU? Perhaps the vrms are overheating a bit and causing it to throttle occasionally?

 

[wasilev.8v]

Can you try undervolting your CPU? Perhaps the vrms are overheating a bit and causing it to throttle occasionally?

You are a literal life saver! I was starting to get really frustrated with this issue. In fact, I downloaded AMD Overdrive and it indeed my CPU was in Turbo mode (overclocked I assume), disabled that option and reduced the voltage by 0.1 (from 1.415 to 1.315), no more throttling.

Thank you for the lightning-fast response!

 

[Supahos]

Common issue with those chips in not top of the line boards your's presented a but different but not surprised