nihsddd.dll is a NIHSDDD 1.8.1f0
belonging to NIHSDDD
from National Instruments Corporation
Non-system processes like nihsddd.dll originate from software you installed on your system. Since most applications store data in your system's registry, it is likely that your registry has suffered fragmentation and accumulated invalid entries which can affect your PC's performance. It is recommended that you check your registry to identify slowdown issues.