The 970, even as nice as it is could be overwhelmed by a heavy number of items in a scene. There are long discussions and so let's keep priors in mind here.
For now, let's get a Speccy report in here as your details are light.
Here's how -> https://www.piriform.com/docs/speccy/using-speccy/publishing-a-speccy-profile-to-the-web
A recent complain was similar to yours but for some odd reason they had a single stick of RAM. That's a drag chute on performance. But the Speccy will tell more.
Remember I'm not going to duplicate the web about variable frame rates or why.
Pc Specs:
Processor: AMD FX(tm)-8350 Eight-Core Processor
(8 CPUs), ~4.0GHz
Memory: 8192MB RAM
GPU: Nvidia GTX 970
Since I bought my new pc i've been getting framedrops every once in a while from 60-80 to an unplayable 10-25 fps. (every 10 secs)
My question is: Are this framedrops because the cpu cant handle such a powerful gpu and it is just not powerful enough or is it because of high temperatures of the cpu that it framedrops everytime it reaches certain temp to keep it working?
I really dont know much about this and would appreciate some help and suggestions, thank you.

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