Why does the PC sometimes start to lag a lot?

Question

Video cards

Hello, lately the PC has started to freeze heavily, mainly when I play something, but it happens during normal work! You have to restart the PC and the lags disappear.
Everything is fine with the PC temperature, I cleaned the PC, changed the thermal paste on the processor and video card, reinstalled Windows too! But the lags remained as they were.
PC specifications:
OC: Microsoft Windows 10 Home.
Motherboard: Biostar B350ET2 (Latest BIOS).
Processor: AMD Ryzen 5 1600.
Video card: GeForce GTX 1050 Ti (4 GB).
RAM: DDR4, 8GBx1pcs, 2400MHz.
Power supply: DEXP DTS-550

Answer 1

During the manifestation of the problem, you need to collect information:
CPU \ RAM load (task manager)
View smart disks ( hdd.by/victoria/) Deal
with installing updates (install)
Remove, disable antivirus.
Find out at what running applications the PC starts to slow down.

Answer 2

Memory test, SMART disk, system logs - that's what you need to watch.
And do not change the thermal paste, and rearrange the Windows.
Windows also reinstalled!

I hope they put it from the original image from Microsoft, and not an assembly from some especially gifted ones?

Answer 3

windows was set to normal?
Is there free space on the C drive, and is there more than a little bit of it?
pagefile not disabled?
HDD or SSD?
If the latter, did you do any "optimizations"?
External media is not connected when the PC starts to "stupid"?
SMART OK?
Memetest passes without problems?
If everything on the list above is normal, then I can recommend LatecyMon \ WhySoSlow