Interesting that this should happen on both computers. Did the slow down happen just after you installed NIS? Have you done a scan for malware? (If you don't have an anti malware program, Lavasoft Ad-Aware Free is a good one. Also, Webroot SpySweeper - not free is good.) When you are not running any programs, go to the Windows Task Manager (Ctrl+Alt+Delete) and look at on the Performance tab. What percentage shows for CPU Usage? Also,on the Applications tab, are there any programs listed there? Have you tried a System Restore? How much RAM do you have on each computer?