30ui.dll is a SIUI.DLL
belonging to Sunplus Inkjet Printer Driver
from Sunplus Technology Inc., Ltd.
Non-system processes like 30ui.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.