NVIDIA graphics card and computer performance issues after installing CUDA?

I have an NVIDIA GeForce GT 640 card in my computer. I wanted to use Davinci Resolve so I installed CUDA. I was told my computer should handle it fine. I had to move a file or two around to get CUDA working but it was a pretty easy install. About a week after I installed it my computer was lagging and I can’t run any of my adobe products or Resolve for more then a few minutes. When I look at my NVIDIA card it says Windows cannot verify the digital signature for the drivers required for this device. A recent or software change might have installed a file that is signed incorrectly or damaged, or that might be malicious software from an unknown source. (Code 52)

The computer is consistently refreshing the icons and such. When I try to use my app screen the computer makes sounds like it’s working really hard and sometimes shuts down. My computer is usually fairly quiet unless I’m rendering video. I’ve gotten a kernal data input error a few times that I haven’t been able to fix yet.I tried updating the driver and rolling back an update but it didn’t make a difference.

Could CUDA be interfering with my graphics card? Should I try reinstalling CUDA? I’m curious to see if anyone else has had any issues like this. Thanks in advance!