[Solved] Sudden FPS Drop in LoL: i3-4160, GTX 750 Ti, MSI H81M-P33, Corsair VS450, 4GB RAM, Win7

Hello, let me introduce my PC hardware first:
Motherboard: MSI H81M-P33 (MS-7817)
Processor: i3-4160 3.6GHz
Graphics: NVIDIA GForce gtx 750 ti, memory size 1024MB
Power supply: CORSAIR VS450
4GB RAM memory 1 chip

Windows 7

Well, after a few days of not using the computer (the computer was on for 2 days) something happened to fps.
Playing League of Legends I have an average of 45 fps, where previously I was 75. I used to have a similar problem, but after resetting the BIOS everything is back to normal, but now it did not help. I scanned Malwarebytes (I cleared the bugs), HD tune showed everything ok in health. I also noticed a lot of hardware errors in the resource monitor.

I have a HWinfo log and some afterburner screenshots.

The CPU drops to 800MHz under load and hence such a weak FPS. Why I do not know - you did not combine in the power profile? Reset bios and possibly insert photos from bios settings.

As for the power profile, I did nothing. It happened overnight. I did a BIOS reset. But it didn't help.

Provide a screen with hardware errors.

screen, I don't know if I did it right

It's probably from using Swap on HDD.

Fire up the throttlestop and set its multiplier to the max, save and turn on. Fire up the built-in TSBench and see if it will keep the timing or it will immediately drop to 800. All power cables will be properly connected to the motherboard?

Could you tell me where this multiplier is?

You give the multipler set to the maximum and mark the bird next to it. THIS is in the main TS window.

I did as you said and it hasn't gone down to 800 not once

Try playing with TS running in the background. Possibly make logs in hwinfo.

Now the fps was a steady 75 and the game ran smoothly. But why without a throttle the foot drops?

I do not know. Maybe the sensors are cheating on the temperature and the board is limiting the CPU power.

Do you have the latest bios version? Maybe it's worth uploading the newest one or re-uploading it when it's already the newest?

The last time, probably a year ago, I did a bios update, I will try to update.
Is it safe to use the throttlestop?

Yes, I am still riding it because I have full control over the CPU multiplier, additionally I am spinning it or doing undervolt (which in principle I do not do because lowering the multiplier is enough for me).

Even though the problem has not completely disappeared, I am using a throttlestop to compensate for the drops. Thank you very much !