Ecran qui s'éteind seul et de manière aléatoi

Un petit problème d'extinction intempestive d'écran, aucun virus détecté, je pense que cela peut être le processeur qui chauffe..qu'en pensez vous?
le log hijackthis est joint juste au cas ou.
merci

Logfile of HijackThis v1.99.1
Scan saved at 16:17:28, on 21/05/2006
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

Running processes:
C:\WINDOWS\System32\smss.exe
C:\WINDOWS\system32\winlogon.exe
C:\WINDOWS\system32\services.exe
C:\WINDOWS\system32\lsass.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Fichiers communs\Symantec Shared\ccSetMgr.exe
C:\Program Files\Fichiers communs\Symantec Shared\SPBBC\SPBBCSvc.exe
C:\Program Files\Fichiers communs\Symantec Shared\ccEvtMgr.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Fichiers communs\Real\Update_OB\realsched.exe
C:\Program Files\QuickTime\qttask.exe
C:\PROGRA~1\Wanadoo\TaskBarIcon.exe
C:\WINDOWS\system32\hkcmd.exe
C:\WINDOWS\system32\igfxpers.exe
C:\Program Files\AntiVir PersonalEdition Classic\avgnt.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\MSN Messenger\msnmsgr.exe
C:\Program Files\AntiVir PersonalEdition Classic\sched.exe
C:\PROGRA~1\Wanadoo\EspaceWanadoo.exe
C:\Program Files\Adobe\Acrobat 6.0\Distillr\acrotray.exe
C:\Program Files\AntiVir PersonalEdition Classic\avguard.exe
C:\Program Files\Symantec AntiVirus\DefWatch.exe
C:\PROGRA~1\Wanadoo\ComComp.exe
C:\WINDOWS\System32\FTRTSVC.exe
C:\Program Files\Extensis\Suitcase 9.2\Suitcase.exe
C:\Program Files\Fichiers communs\Microsoft Shared\VS7DEBUG\MDM.EXE
C:\Program Files\MSN Toolbar Suite\DS\02.05.0001.1119\fr-fr\bin\WindowsSearch.exe
C:\PROGRA~1\Wanadoo\Toaster.exe
C:\PROGRA~1\Wanadoo\Inactivity.exe
C:\Program Files\Symantec AntiVirus\Rtvscan.exe
C:\PROGRA~1\Wanadoo\PollingModule.exe
C:\WINDOWS\System32\ALERTM~1\ALERTM~1.EXE
C:\PROGRA~1\INCRED~1\bin\IMApp.exe
C:\Program Files\MSN Toolbar Suite\DS\02.05.0001.1119\fr-fr\bin\WindowsSearchIndexer.exe
C:\WINDOWS\system32\wuauclt.exe
C:\PROGRA~1\Wanadoo\Watch.exe
C:\Documents and Settings\Administrateur\Mes documents\mes telechargements\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Bar = https://www.bing.com/?FORM=TOOLBR&cc=fr&toHttps=1&redig=4527FFF1C12746FC9EDB535C75E80ECC
R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = https://www.google.fr
R1 - HKCU\Software\Microsoft\Internet Explorer\SearchURL,(Default) = https://www.bing.com/?FORM=TOOLBR&cc=fr&toHttps=1&redig=4527FFF1C12746FC9EDB535C75E80ECC
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Window Title = Wanadoo
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Liens
R3 - URLSearchHook: Search Class - {08C06D61-F1F3-4799-86F8-BE1A89362C85} - C:\PROGRA~1\Wanadoo\SEARCH~1.DLL
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Adobe\Acrobat 6.0\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {59879FA4-4790-461c-A1CC-4EC4DE4CA483} - (no file)
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - c:\program files\google\googletoolbar2.dll
O2 - BHO: AcroIEToolbarHelper Class - {AE7CD045-E861-484f-8273-0445EE161910} - C:\Program Files\Adobe\Acrobat 6.0\Acrobat\AcroIEFavClient.dll
O2 - BHO: Barre d'outils MSN Search Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\MSN Toolbar Suite\TB\02.05.0000.1105\fr-fr\msntb.dll
O3 - Toolbar: Adobe PDF - {47833539-D0C5-4125-9FA8-0819E2EAAC93} - C:\Program Files\Adobe\Acrobat 6.0\Acrobat\AcroIEFavClient.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - c:\program files\google\googletoolbar2.dll
O3 - Toolbar: Yahoo! Toolbar - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\Program Files\Yahoo!\Companion\Installs\cpn\yt.dll
O3 - Toolbar: Easy-WebPrint - {327C2873-E90D-4c37-AA9D-10AC9BABA46C} - C:\Program Files\Canon\Easy-WebPrint\Toolband.dll
O3 - Toolbar: Barre d'outils MSN Search - {BDAD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\MSN Toolbar Suite\TB\02.05.0000.1105\fr-fr\msntb.dll
O4 - HKLM\..\Run: [TkBellExe] "C:\Program Files\Fichiers communs\Real\Update_OB\realsched.exe" -osboot
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [WOOWATCH] C:\PROGRA~1\Wanadoo\Watch.exe
O4 - HKLM\..\Run: [WOOTASKBARICON] C:\PROGRA~1\Wanadoo\GestMaj.exe TaskBarIcon.exe
O4 - HKLM\..\Run: [UserFaultCheck] %systemroot%\system32\dumprep 0 -u
O4 - HKLM\..\Run: [igfxtray] C:\WINDOWS\system32\igfxtray.exe
O4 - HKLM\..\Run: [igfxhkcmd] C:\WINDOWS\system32\hkcmd.exe
O4 - HKLM\..\Run: [igfxpers] C:\WINDOWS\system32\igfxpers.exe
O4 - HKLM\..\Run: [avgnt] "C:\Program Files\AntiVir PersonalEdition Classic\avgnt.exe" /min
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [IncrediMail] C:\PROGRA~1\INCRED~1\bin\IncMail.exe /c
O4 - HKCU\..\Run: [WOOKIT] C:\PROGRA~1\Wanadoo\Shell.exe appLaunchClientZone.shl|DEFAULT=cnx|PARAM=
O4 - HKCU\..\Run: [msnmsgr] "C:\Program Files\MSN Messenger\msnmsgr.exe" /background
O4 - Global Startup: Adobe Gamma Loader.lnk = C:\Program Files\Fichiers communs\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Assistant d'Acrobat.lnk = C:\Program Files\Adobe\Acrobat 6.0\Distillr\acrotray.exe
O4 - Global Startup: Suitcase Startup.lnk = ?
O4 - Global Startup: Windows Desktop Search.lnk = C:\Program Files\MSN Toolbar Suite\DS\02.05.0001.1119\fr-fr\bin\WindowsSearch.exe
O8 - Extra context menu item: &Add animation to IncrediMail Style Box - C:\PROGRA~1\INCRED~1\bin\resources\WebMenuImg.htm
O8 - Extra context menu item: &Google Search - res://c:\program files\google\GoogleToolbar2.dll/cmsearch.html
O8 - Extra context menu item: &MSN Search - res://C:\Program Files\MSN Toolbar Suite\TB\02.05.0000.1105\fr-fr\msntb.dll/search.htm
O8 - Extra context menu item: &Translate English Word - res://c:\program files\google\GoogleToolbar2.dll/cmwordtrans.html
O8 - Extra context menu item: Backward Links - res://c:\program files\google\GoogleToolbar2.dll/cmbacklinks.html
O8 - Extra context menu item: Cached Snapshot of Page - res://c:\program files\google\GoogleToolbar2.dll/cmcache.html
O8 - Extra context menu item: E&xporter vers Microsoft Excel - res://C:\PROGRA~1\MICROS~3\OFFICE11\EXCEL.EXE/3000
O8 - Extra context menu item: Ouvrir dans un nouvel onglet d'arrière-plan - res://C:\Program Files\MSN Toolbar Suite\TAB\02.05.0000.1105\fr-fr\msntabres.dll/229?1542573573354519933e2ff1c1a09d
O8 - Extra context menu item: Ouvrir dans un nouvel onglet de premier plan - res://C:\Program Files\MSN Toolbar Suite\TAB\02.05.0000.1105\fr-fr\msntabres.dll/230?1542573573354519933e2ff1c1a09d
O8 - Extra context menu item: Similar Pages - res://c:\program files\google\GoogleToolbar2.dll/cmsimilar.html
O8 - Extra context menu item: Translate Page into English - res://c:\program files\google\GoogleToolbar2.dll/cmtrans.html
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_04\bin\npjpi150_04.dll
O9 - Extra 'Tools' menuitem: Console Java (Sun) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.5.0_04\bin\npjpi150_04.dll
O9 - Extra button: Recherche - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~3\OFFICE11\REFIEBAR.DLL
O9 - Extra button: Messager Wanadoo - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\PROGRA~1\WANADO~1\Wanadoo Messager.exe (file missing)
O9 - Extra 'Tools' menuitem: Messager Wanadoo - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\PROGRA~1\WANADO~1\Wanadoo Messager.exe (file missing)
O9 - Extra button: Wanadoo - {1462651F-F4BA-4C76-A001-C4284D0FE16E} - https://www.orange.fr/portail (file missing) (HKCU)
O16 - DPF: {FD40EC41-D860-4579-8BA4-52671A45C71C} (AxHtChat Class) - http://images.goa.com/it/Woo2/fr/chat/nPaxChat.cab
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - "C:\PROGRA~1\MSNMES~1\msgrapp.dll" (file missing)
O18 - Filter: text/html - {2AB289AE-4B90-4281-B2AE-1F4BB034B647} - (no file)
O20 - Winlogon Notify: igfxcui - C:\WINDOWS\SYSTEM32\igfxdev.dll
O20 - Winlogon Notify: NavLogon - C:\WINDOWS\system32\NavLogon.dll
O23 - Service: AntiVir PersonalEdition Classic Scheduler (AntiVirScheduler) - Avira GmbH - C:\Program Files\AntiVir PersonalEdition Classic\sched.exe
O23 - Service: AntiVir PersonalEdition Classic Guard (AntiVirService) - AVIRA GmbH - C:\Program Files\AntiVir PersonalEdition Classic\avguard.exe
O23 - Service: Symantec Event Manager (ccEvtMgr) - Symantec Corporation - C:\Program Files\Fichiers communs\Symantec Shared\ccEvtMgr.exe
O23 - Service: Symantec Password Validation (ccPwdSvc) - Symantec Corporation - C:\Program Files\Fichiers communs\Symantec Shared\ccPwdSvc.exe
O23 - Service: Symantec Settings Manager (ccSetMgr) - Symantec Corporation - C:\Program Files\Fichiers communs\Symantec Shared\ccSetMgr.exe
O23 - Service: Symantec AntiVirus Definition Watcher (DefWatch) - Symantec Corporation - C:\Program Files\Symantec AntiVirus\DefWatch.exe
O23 - Service: France Telecom Routing Table Service (FTRTSVC) - France Telecom - C:\WINDOWS\System32\FTRTSVC.exe
O23 - Service: SAVRoam (SavRoam) - symantec - C:\Program Files\Symantec AntiVirus\SavRoam.exe
O23 - Service: Symantec Network Drivers Service (SNDSrvc) - Symantec Corporation - C:\Program Files\Fichiers communs\Symantec Shared\SNDSrvc.exe
O23 - Service: Symantec SPBBCSvc (SPBBCSvc) - Symantec Corporation - C:\Program Files\Fichiers communs\Symantec Shared\SPBBC\SPBBCSvc.exe
O23 - Service: Symantec AntiVirus - Symantec Corporation - C:\Program Files\Symantec AntiVirus\Rtvscan.exe