Ordinateur qui rame

Bonjour,
depuis quelques temps mon ordi rame et plante de temps en temps, c'est un packard bell, AMD64athlon*2 4000+, 2048mo de rame, disque dur320 GO, avec vista.

Je pense avoir un virus mais spyware ne trouve rien, avista non plus...
on m'a conseillé de défragmenter, quand je le fais, un message comme quoi il n' y a pas besoin de le faire apparait...

j'ai utilisé c-cleaner aussi.

donc voici le scan hijack:
Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 14:35:38, on 30/03/2008
Platform: Windows Vista (WinNT 6.00.1904)
MSIE: Internet Explorer v7.00 (7.00.6000.16609)
Boot mode: Normal

Running processes:
C:\Windows\system32\taskeng.exe
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Program Files\Windows Defender\MSASCui.exe
C:\Windows\RtHDVCpl.exe
C:\Program Files\Common Files\Roxio Shared\9.0\SharedCOM\RoxWatchTray9.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe
C:\Program Files\Java\jre1.6.0_05\bin\jusched.exe
C:\Windows\System32\rundll32.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktopIndex.exe
C:\Program Files\Avira\AntiVir PersonalEdition Classic\avgnt.exe
C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Program Files\Packard Bell\SetUpMyPC\SmpSys.exe
C:\Windows\ehome\ehtray.exe
C:\Program Files\Windows Live\Messenger\msnmsgr.exe
C:\Program Files\Creative\Creative Live! Cam\Live! Cam Manager\CTLCMgr.exe
C:\Program Files\Google\GoogleToolbarNotifier\1.2.1128.5462\GoogleToolbarNotifier.exe
C:\Program Files\Common Files\Roxio Shared\9.0\SharedCOM\CPSHelpRunner.exe
C:\Program Files\Google\Google Desktop Search\GoogleDesktopCrawl.exe
C:\Windows\ehome\ehmsas.exe
C:\Program Files\OpenOffice.org 2.3\program\soffice.exe
C:\Program Files\OpenOffice.org 2.3\program\soffice.BIN
C:\Program Files\Windows Mail\WinMail.exe
C:\Program Files\Internet Explorer\IEUser.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Common Files\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Windows\system32\Macromed\Flash\FlashUtil9e.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R0 - HKLM\Software\Microsoft\Internet Explorer\Search,SearchAssistant =
R0 - HKLM\Software\Microsoft\Internet Explorer\Search,CustomizeSearch =
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName =
O1 - Hosts: ::1 localhost
O2 - BHO: Aide pour le lien d'Adobe PDF Reader - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O2 - BHO: (no name) - {7E853D72-626A-48EC-A868-BA8D5E23E045} - (no file)
O2 - BHO: Programme d'aide de l'Assistant de connexion Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O2 - BHO: Windows Live Toolbar Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O2 - BHO: Browser Address Error Redirector - {CA6319C0-31B7-401E-A518-A07C3DB8F777} - C:\Program Files\Google\Google_BAE\BAE.dll
O3 - Toolbar: Windows Live Toolbar - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O4 - HKLM\..\Run: [Windows Defender] %ProgramFiles%\Windows Defender\MSASCui.exe -hide
O4 - HKLM\..\Run: [RtHDVCpl] RtHDVCpl.exe
O4 - HKLM\..\Run: [NvSvc] RUNDLL32.EXE C:\Windows\system32\nvsvc.dll,nvsvcStart
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\Windows\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\Windows\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [RoxWatchTray] "C:\Program Files\Common Files\Roxio Shared\9.0\SharedCOM\RoxWatchTray9.exe"
O4 - HKLM\..\Run: [Google Desktop Search] "C:\Program Files\Google\Google Desktop Search\GoogleDesktop.exe" /startup
O4 - HKLM\..\Run: [toolbar_eula_launcher] C:\Program Files\Packard Bell\GOOGLE_EULA\EULALauncher.exe
O4 - HKLM\..\Run: [SunJavaUpdateSched] "C:\Program Files\Java\jre1.6.0_05\bin\jusched.exe"
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "C:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [avgnt] "C:\Program Files\Avira\AntiVir PersonalEdition Classic\avgnt.exe" /min
O4 - HKLM\..\Run: [!AVG Anti-Spyware] "C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\avgas.exe" /minimized
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKCU\..\Run: [SmpcSys] C:\Program Files\Packard Bell\SetUpMyPC\SmpSys.exe
O4 - HKCU\..\Run: [ehTray.exe] C:\Windows\ehome\ehTray.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [Creative Live! Cam Manager] "C:\Program Files\Creative\Creative Live! Cam\Live! Cam Manager\CTLCMgr.exe"
O4 - HKCU\..\Run: [Magentic] C:\PROGRA~1\Magentic\bin\Magentic.exe /c
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\1.2.1128.5462\GoogleToolbarNotifier.exe
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'SERVICE LOCAL')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'SERVICE RÉSEAU')
O4 - HKUS\S-1-5-18\..\Run: [Picasa Media Detector] C:\Program Files\Picasa2\PicasaMediaDetector.exe (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [Picasa Media Detector] C:\Program Files\Picasa2\PicasaMediaDetector.exe (User 'Default user')
O4 - Startup: OpenOffice.org 2.3.lnk = C:\Program Files\OpenOffice.org 2.3\program\quickstart.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office\OSA9.EXE
O8 - Extra context menu item: &Windows Live Search - res://C:\Program Files\Windows Live Toolbar\msntb.dll/search.htm
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra button: Ajout Direct - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files\Windows Live\Writer\WriterBrowserExtension.dll
O9 - Extra 'Tools' menuitem: &Ajout Direct dans Windows Live Writer - {219C3416-8CB2-491a-A3C7-D9FCDDC9D600} - C:\Program Files\Windows Live\Writer\WriterBrowserExtension.dll
O16 - DPF: {D27CDB6E-AE6D-11CF-96B8-444553540000} (Shockwave Flash Object) - http://fpdownload2.macromedia.com/get/shockwave/cabs/flash/swflash.cab
O20 - AppInit_DLLs: C:\PROGRA~1\Google\GOOGLE~3\GOEC62~1.DLL
O23 - Service: AntiVir PersonalEdition Classic Scheduler (AntiVirScheduler) - Avira GmbH - C:\Program Files\Avira\AntiVir PersonalEdition Classic\sched.exe
O23 - Service: AntiVir PersonalEdition Classic Guard (AntiVirService) - Avira GmbH - C:\Program Files\Avira\AntiVir PersonalEdition Classic\avguard.exe
O23 - Service: AVG Anti-Spyware Guard - GRISOFT s.r.o. - C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: GoogleDesktopManager - Google - C:\Program Files\Google\Google Desktop Search\GoogleDesktopManager.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\1050\Intel 32\IDriverT.exe
O23 - Service: Planificateur LiveUpdate automatique - Unknown owner - C:\Program Files\Symantec\LiveUpdate\ALUSchedulerSvc.exe (file missing)
O23 - Service: RoxMediaDB9 - Sonic Solutions - C:\Program Files\Common Files\Roxio Shared\9.0\SharedCOM\RoxMediaDB9.exe
O23 - Service: Roxio Hard Drive Watcher 9 (RoxWatch9) - Sonic Solutions - C:\Program Files\Common Files\Roxio Shared\9.0\SharedCOM\RoxWatch9.exe
O23 - Service: stllssvr - MicroVision Development, Inc. - C:\Program Files\Common Files\SureThing Shared\stllssvr.exe
O23 - Service: Symantec Core LC - Symantec Corporation - C:\Program Files\Common Files\Symantec Shared\CCPD-LC\symlcsvc.exe

qu'en pensez vous?
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