2005 dell notebook has odd behavior. runs fine for awhile. online function is ok. than any key entry results in multiple "search" pop-up windows. about 1/2 of the keyboard keys do not function than. restart in safemode and all is well for awhile and than same popup issues start. thought it was 3rd party bug/software causing issue but it shows up in safemode. tried many cures, norton scan, avg scan, stinger scan. computer works on restart. am close to reinstall but wanted to hear if anyone else had any thoughts on finding virus.