ah, well.. I was surfing the web and just suddenly, my computer turns off.. I thought it was only a blackout but there was none.. I turned it on again.. Fortunately, it starts up normally.. I forgot about the whole thing but then, just 10-20 minutes later, it turns off again.. ö I repeated what I did, but still, it turns off again after only a few minutes.. what's wrong with my computer..?

here's the HijackThis Log:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 11:33:16 AM, on 5/17/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16640)
Boot mode: Normal

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\AlienGUIse\wbload.exe
C:\WINDOWS\system32\spoolsv.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\VIA\RAID\raid_tool.exe
C:\Program Files\Analog Devices\Core\smax4pnp.exe
C:\Program Files\Analog Devices\SoundMAX\Smax4.exe
C:\Program Files\BitDefender\BitDefender 2008\bdagent.exe
C:\Program Files\ScanSoft\OmniPageSE2.0\OpwareSE2.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\Adobe\Reader 8.0\Reader\reader_sl.exe
C:\WINDOWS\system32\WTablet\TabUserW.exe
C:\Program Files\Yahoo!\Messenger\ymsgr_tray.exe
C:\Program Files\Bonjour\mDNSResponder.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\Tablet.exe
C:\Program Files\Common Files\BitDefender\BitDefender Communicator\xcommsvr.exe
C:\Program Files\Zumie\zumie.exe
C:\Program Files\Common Files\BitDefender\BitDefender Update Service\livesrv.exe
C:\Program Files\BitDefender\BitDefender 2008\vsserv.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Zumie\zumie.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe
C:\WINDOWS\system32\wuauclt.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = about:blank
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Search_URL = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R0 - HKLM\Software\Microsoft\Internet Explorer\Main,Start Page = http://go.microsoft.com/fwlink/?LinkId=69157
R1 - HKCU\Software\Microsoft\Windows\CurrentVersion\Internet Settings,ProxyOverride = *.local
R3 - URLSearchHook: Yahoo! ¤u¨ă¦C - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\PROGRA~1\Yahoo!\Companion\Installs\cpn\yt.dll
O2 - BHO: &Yahoo! Toolbar Helper - {02478D38-C3F9-4efb-9B51-7695ECA05670} - C:\PROGRA~1\Yahoo!\Companion\Installs\cpn\yt.dll
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Megaupload Toolbar - {4E7BD74F-2B8D-469E-CCB0-B130EEDBE97C} - C:\PROGRA~1\MEGAUP~1\MEGAUP~1.DLL
O3 - Toolbar: BitDefender Toolbar - {381FFDE8-2394-4f90-B10D-FC6124A40F8C} - C:\Program Files\BitDefender\BitDefender 2008\IEToolbar.dll
O3 - Toolbar: Yahoo! ¤u¨ă¦C - {EF99BD32-C1FB-11D2-892F-0090271D4F88} - C:\PROGRA~1\Yahoo!\Companion\Installs\cpn\yt.dll
O3 - Toolbar: Megaupload Toolbar - {4E7BD74F-2B8D-469E-CCB0-B130EEDBE97C} - C:\PROGRA~1\MEGAUP~1\MEGAUP~1.DLL
O4 - HKLM\..\Run: [RaidTool] C:\Program Files\VIA\RAID\raid_tool.exe
O4 - HKLM\..\Run: [High Definition Audio Property Page Shortcut] HDAShCut.exe
O4 - HKLM\..\Run: [SoundMAXPnP] C:\Program Files\Analog Devices\Core\smax4pnp.exe
O4 - HKLM\..\Run: [SoundMAX] "C:\Program Files\Analog Devices\SoundMAX\Smax4.exe" /tray
O4 - HKLM\..\Run: [BitDefender Antiphishing Helper] "C:\Program Files\BitDefender\BitDefender 2008\IEShow.exe"
O4 - HKLM\..\Run: [BDAgent] "C:\Program Files\BitDefender\BitDefender 2008\bdagent.exe"
O4 - HKLM\..\Run: [OpwareSE2] "C:\Program Files\ScanSoft\OmniPageSE2.0\OpwareSE2.exe"
O4 - HKLM\..\Run: [OPSE reminder] "C:\Program Files\ScanSoft\OmniPageSE2.0\EregEng\Ereg.exe" -r "C:\Program Files\ScanSoft\OmniPageSE2.0\EregEng\ereg.ini"
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [Yahoo! Pager] "C:\Program Files\Yahoo!\Messenger\YahooMessenger.exe" -quiet
O4 - Startup: Adobe Gamma.lnk = C:\Program Files\Common Files\Adobe\Calibration\Adobe Gamma Loader.exe
O4 - Global Startup: Adobe Reader Speed Launch.lnk = C:\Program Files\Adobe\Reader 8.0\Reader\reader_sl.exe
O4 - Global Startup: Adobe Reader Synchronizer.lnk = C:\Program Files\Adobe\Reader 8.0\Reader\AdobeCollabSync.exe
O4 - Global Startup: TabUserW.exe.lnk = C:\WINDOWS\system32\WTablet\TabUserW.exe
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~2\Office12\REFIEBAR.DLL
O9 - Extra button: (no name) - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - C:\WINDOWS\Network Diagnostic\xpnetdiag.exe
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - C:\Program Files\Messenger\msmsgs.exe
O23 - Service: Adobe LM Service - Adobe Systems - C:\Program Files\Common Files\Adobe Systems Shared\Service\Adobelmsvc.exe
O23 - Service: ##Id_String1.6844F930_1628_4223_B5CC_5BB94B879762## (Bonjour Service) - Apple Computer, Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: FLEXnet Licensing Service - Macrovision Europe Ltd. - C:\Program Files\Common Files\Macrovision Shared\FLEXnet Publisher\FNPLicensingService.exe
O23 - Service: BitDefender Desktop Update Service (LIVESRV) - BitDefender SRL - C:\Program Files\Common Files\BitDefender\BitDefender Update Service\livesrv.exe
O23 - Service: TabletService - Wacom Technology, Corp. - C:\WINDOWS\system32\Tablet.exe
O23 - Service: BitDefender Virus Shield (VSSERV) - BitDefender S.R.L. - C:\Program Files\BitDefender\BitDefender 2008\vsserv.exe
O23 - Service: BitDefender Communicator (XCOMM) - BitDefender - C:\Program Files\Common Files\BitDefender\BitDefender Communicator\xcommsvr.exe
O23 - Service: Zumie Search Service - Zumie.com - C:\Program Files\Zumie\zumie.exe

--
End of file - 6153 bytes


Thanks for whoever helps.. ^^