Hi, and welcome to Geeks to Go! The "System" entry in Taskmanager includes much that it is not designed to reveal. To get a clearer picture of what is going on, I suggest Sysinternals free Process Explorer. Get it here: http://www.microsoft...ssExplorer.mspx
(Download link at bottom of page.) A click on the main column header, "Process," will switch to a "Process Tree" view, and those processes running under "System" will become apparent. If you choose CPU Time as one of the options under View>Select columns.., a click on that column header will sort the processes accordingly. Your culprit should be near the top. A double click on any process will bring up a "Properties" display in which much more information is available. Note especially the amount of usage by "Interrupts." If high, the root of the problem may be hardware related.
For information about the various processes, here are some good places to check: http://www.ppedia.com/http://www.fileresearchcenter.com/http://www.answersth...es/tasklist.htmhttp://www.kephyr.com/filedb/index.phphttp://www.what-process.com/lists.aspxhttp://exelib.com/http://www.processlibrary.com/
Here is a place to check any questionable file. It gets scanned by almost all available "anti-" tools:http://www.virustota.../en/indexx.html
If at any time in your investigation you have reason to suspect that malware is involved, go here:http://www.geekstogo..._Log-t2852.html
Follow the self-help instructions, and if not completely effective (all scans return negative findings on rerun),
post a HiJackThis log according to the instructions in the above link. Good luck, and please post back with your progress.