I am using Windows Vista Home Basic Service Pack 1. My computer is powered by a Intel 2 Quad processor 2.40GHz , my computer has 2GB of ram.

-I do not know why but, of late, my computer has been hanging or restarting randomly when I was in the middle of surfing the internet or playing games. On several occasions, there would be blue screens as well. See this: https://i.servimg.com/u/f89/13/69/31/58/bluesc11.jpg for a screenshot of the details of the bluescreen problem. There was no error message shown before the restarts. I do not use my computer for more than 5 hours a day and do not overclock my computer.

-I have reformatted my computer several times but the problem did not seem to go away.

-I seek some advice and decreased the maximum processor usage of my computer from 100% to 70%. This was because I heard that Vista is power-hungry, thus this would cause my processor to overheat and the computer would restart. After this, the computer did not give me so much problem. However, this problem seems to pop-up once in 20-30 days or... randomly. But the problem did not come so often as before. Last time, it would come 2-3 days.

-I have scanned my computer for viruses with eset's online scanner and avast antivirus home edition and nothing was found. However, I noticed that eset's scanner would stop working(crash) before the scan could be completed. I do not know why as I have turned off my antivirus,avast home edition, before scanning.
But, avast home edition, which is the antivirus that I am using, includes a screensaver that scans my computer. I observed that the scans were successfully completed by the screensaver. This eliminates the possibility that avast could have caused the random restarts and hangs while scanning a particular file.

-I have checked the startup processes for one that scheduled a shutdown on startup but none was found.

-I have also checked the Task Scheduler and services.msc for any signs of a scheduled shutdown but none were found.

-I have performed a chkdsk of the C: partition, sfc/scannow and a scan with HijackThis. These were done with administrator privileges. The log is displayed below and the screen shots are shown here: https://i.servimg.com/u/f89/13/69/31/58/chkdsk11.jpg(chkdsk) and here: https://i.servimg.com/u/f89/13/69/31/58/scanno10.jpg(sfc/scannow) .

Could a computing expert help to resolve my problem please? Thank you.

Code:

Logfile of Trend Micro HijackThis v2.0.2
Scan saved at 4:04:05 PM, on 5/7/2009
Platform: Windows Vista SP1 (WinNT 6.00.1905)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
Boot mode: Normal

Running processes:
C:\Windows\system32\Dwm.exe
C:\Windows\Explorer.EXE
C:\Program Files\Hewlett-Packard\On-Screen OSD Indicator\OSD.exe
C:\WINDOWS\RtHDVCpl.exe
C:\Program Files\Unlocker\UnlockerAssistant.exe
C:\Program Files\Intel\Intel Matrix Storage Manager\IAAnotif.exe
C:\WINDOWS\System32\rundll32.exe
C:\WINDOWS\System32\rundll32.exe
C:\Program Files\Alwil Software\Avast4\ashDisp.exe
C:\Program Files\HP\HP Software Update\hpwuSchd2.exe
C:\Program Files\Windows Sidebar\sidebar.exe
C:\Windows\system32\taskeng.exe
C:\Program Files\Windows Media Player\wmpnscfg.exe
C:\Windows\System32\mobsync.exe
C:\hp\kbd\kbd.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Windows\system32\conime.exe
C:\Program Files\Microsoft Office\OFFICE11\WINWORD.EXE
C:\Windows\system32\SearchFilterHost.exe
C:\Program Files\Trend Micro\HijackThis\HijackThis.exe

R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://ie.redirect.hp.com/svs/rdr?TYPE=3&tp=iehome&locale=en_sg&c=81&bd=Presario&pf=desktop
R1 - HKCU\Software\Microsoft\Internet Explorer\Main,Search Page = http://go.microsoft.com/fwlink/?LinkId=54896
R1 - HKLM\Software\Microsoft\Internet Explorer\Main,Default_Page_URL = http://ie.redirect.hp.com/svs/rdr?TYPE=3&tp=iehome&locale=en_sg&c=81&bd=Presario&pf=desktop
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://ie.redirect.hp.com/svs/rdr?TYPE=3&tp=iehome&locale=en_sg&c=81&bd=Presario&pf=desktop
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: AcroIEHelperStub - {18DF081C-E8AD-4283-A596-FA578C2EBDC3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelperShim.dll
O2 - BHO: (no name) - {5C255C8A-E604-49b4-9D64-90988571CECB} - (no file)
O2 - BHO: NCO 2.0 IE BHO - {602ADB0E-4AFF-4217-8AA1-95DAC4DFA408} - (no file)
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O2 - BHO: Windows Live Sign-in Helper - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Program Files\Common Files\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O3 - Toolbar: (no name) - {7FEBEFE3-6B19-4349-98D2-FFB09D4B49CA} - (no file)
O4 - HKLM\..\Run: [KBD] C:\HP\KBD\KbdStub.EXE
O4 - HKLM\..\Run: [OsdMaestro] "C:\Program Files\Hewlett-Packard\On-Screen OSD Indicator\OSD.exe"
O4 - HKLM\..\Run: [RtHDVCpl] RtHDVCpl.exe
O4 - HKLM\..\Run: [UnlockerAssistant] "C:\Program Files\Unlocker\UnlockerAssistant.exe" -H
O4 - HKLM\..\Run: [IAAnotif] "C:\Program Files\Intel\Intel Matrix Storage Manager\Iaanotif.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: [avast!] C:\PROGRA~1\ALWILS~1\Avast4\ashDisp.exe
O4 - HKLM\..\Run: [HP Software Update] C:\Program Files\HP\HP Software Update\HPWuSchd2.exe
O4 - HKCU\..\Run: [Sidebar] C:\Program Files\Windows Sidebar\sidebar.exe /autoRun
O4 - HKUS\S-1-5-19\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-19\..\Run: [WindowsWelcomeCenter] rundll32.exe oobefldr.dll,ShowWelcomeCenter (User 'LOCAL SERVICE')
O4 - HKUS\S-1-5-20\..\Run: [Sidebar] %ProgramFiles%\Windows Sidebar\Sidebar.exe /detectMem (User 'NETWORK SERVICE')
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~3\OFFICE11\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_01\bin\ssv.dll
O9 - Extra button: Research - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - C:\PROGRA~1\MICROS~3\OFFICE11\REFIEBAR.DLL
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\wpclsp.dll
O13 - Gopher Prefix:
O16 - DPF: {7530BFB8-7293-4D34-9923-61A11451AFC5} - http://download.eset.com/special/eos/OnlineScanner.cab
O23 - Service: avast! iAVS4 Control Service (aswUpdSv) - ALWIL Software - C:\Program Files\Alwil Software\Avast4\aswUpdSv.exe
O23 - Service: avast! Antivirus - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashServ.exe
O23 - Service: avast! Mail Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashMaiSv.exe
O23 - Service: avast! Web Scanner - ALWIL Software - C:\Program Files\Alwil Software\Avast4\ashWebSv.exe
O23 - Service: GameConsoleService - WildTangent, Inc. - C:\Program Files\HP Games\My HP Game Console\GameConsoleService.exe
O23 - Service: HP Health Check Service - Hewlett-Packard - c:\Program Files\Hewlett-Packard\HP Health Check\hphc_service.exe
O23 - Service: Intel(R) Matrix Storage Event Monitor (IAANTMON) - Intel Corporation - C:\Program Files\Intel\Intel Matrix Storage Manager\Iaantmon.exe
O23 - Service: LightScribeService Direct Disc Labeling Service (LightScribeService) - Hewlett-Packard Company - c:\Program Files\Common Files\LightScribe\LSSrvc.exe
O23 - Service: wampapache - Apache Software Foundation - c:\wamp\bin\apache\apache2.2.11\bin\httpd.exe
O23 - Service: wampmysqld - Unknown owner - c:\wamp\bin\mysql\mysql5.1.32\bin\mysqld.exe

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