Mouse stuttering and other hardware lags are to be expected if the Benchmark is worth its salt. If you can multi task while a benchmark is running that benchmark isnt doing a very good job. Would you expect a high performance car to have the same 0-60 properties when you put a horse trailer behind it with 6 horses in it?
As already stated to get accurate benchmark results all background apps should be closed including Sonic Studio and Origin.
svloadsense is part of sonic studio.
“Two things are infinite: the universe and human stupidity, I'm not sure about the former” ~ Albert Einstein