My advice would be to lower your CPU frequency, or do anything that can make your computer stable under OCCT.

OCCT stresses components alot. If an error was detected, your computer can generate those. they may happen everytime, usually under heavy loads. Thus, by ignoring this warning, you can have unexpected behaviour, for instance while playing, or while encoding a video...

Sometimes, this error isn't noticeable ( for instance, if in one frame of your favorite fps one point is not at the right spot, you probably won't notice it, and it won't crash your game). Sometimes, it is really noticeable ( if it happens in a critical CPU process, blue screen ! or if you were encoding, your video file will be corrupted).

I really advise you not to ignore OCCT's warning.