Sounds like a virus or core OS problem to me.
What are your hardware specs?
What OS version are you running and how long has it been since you did a FULL CLEAN install of the OS?
What, if any, anti virus or malware monitoring utility are you running? Have you updated your virus and malware definitions and then run FULL system scans? Use of the system host processes is a common method used by malicious software.
This is almost certainly not a memory problem, but a software or infection problem.