durbanboy 0 Newbie Poster

My computer shuts down for no reason at all. It does not matter what I am doing, but is more prone to do it on 'secure' sites - eg. Internet Banking.
I thought I had a hardware problem, so have replaced motherboard, processor and memory. It ran fine for 3 weeks, then started up again.
I use Registry Mechanic, Bug Doctor, AVG Anti-Virus and AVG Anti-Spyware.

I ran 'Hijackthis' and here is the log:

Logfile of HijackThis v1.99.1
Scan saved at 18:24:35, on 08/07/2008
Platform: Windows XP SP2 (WinNT 5.01.2600)
MSIE: Internet Explorer v7.00 (7.00.6000.16674)

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\Ati2evxx.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
C:\WINDOWS\system32\Ati2evxx.exe
C:\WINDOWS\Explorer.EXE
C:\PROGRA~1\Grisoft\AVG7\avgcc.exe
C:\Program Files\Lexmark X1100 Series\lxbkbmgr.exe
C:\Program Files\Java\jre1.6.0_05\bin\jusched.exe
C:\Program Files\Lexmark X1100 Series\lxbkbmon.exe
C:\Program Files\Microsoft Office\Office12\GrooveMonitor.exe
C:\WINDOWS\CTHELPER.EXE
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\MOM.exe
C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
C:\Garmin\gStart.exe
C:\WINDOWS\system32\LEXBCES.EXE
C:\WINDOWS\system32\LEXPPS.EXE
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\ccc.exe
C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
C:\PROGRA~1\Grisoft\AVG7\avgemc.exe
C:\Program Files\Bonjour\mDNSResponder.exe
C:\Program Files\Nero\Nero8\Nero BackItUp\NBService.exe
C:\WINDOWS\system32\IoctlSvc.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\MsPMSPSv.exe
C:\WINDOWS\system32\SearchIndexer.exe
C:\WINDOWS\System32\svchost.exe
C:\Program Files\Windows Live\Messenger\usnsvc.exe
C:\Program Files\Internet Explorer\iexplore.exe
C:\Program Files\Common Files\Microsoft Shared\Windows Live\WLLoginProxy.exe
C:\Program Files\HijackThis\HijackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.co.uk/
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
O2 - BHO: Adobe PDF Reader Link Helper - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Program Files\Common Files\Adobe\Acrobat\ActiveX\AcroIEHelper.dll
O2 - BHO: Groove GFS Browser Helper - {72853161-30C5-4D22-B7F9-0BBC1D38A37E} - C:\PROGRA~1\MICROS~2\Office12\GRA8E1~1.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: Windows Live Sign-in Helper - {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: Google Toolbar Notifier BHO - {AF69DE43-7D58-4638-B6FA-CE66B5AD205D} - C:\Program Files\Google\GoogleToolbarNotifier\3.0.1225.9868\swg.dll
O2 - BHO: Windows Live Toolbar Helper - {BDBD1DAD-C946-4A17-ADC1-64B5B4FF55D0} - C:\Program Files\Windows Live Toolbar\msntb.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
O3 - Toolbar: (no name) - {07B18EA9-A523-4961-B6BB-170DE4475CCA} - (no file)
O4 - HKLM\..\Run: [AVG7_CC] C:\PROGRA~1\Grisoft\AVG7\avgcc.exe /STARTUP
O4 - HKLM\..\Run: [Lexmark X1100 Series] "C:\Program Files\Lexmark X1100 Series\lxbkbmgr.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: [Sony Ericsson PC Suite] "C:\Program Files\Sony Ericsson\Mobile2\Application Launcher\Application Launcher.exe" /startoptions
O4 - HKLM\..\Run: [NeroFilterCheck] C:\Program Files\Common Files\Nero\Lib\NeroCheck.exe
O4 - HKLM\..\Run: [NBKeyScan] "C:\Program Files\Nero\Nero8\Nero BackItUp\NBKeyScan.exe"
O4 - HKLM\..\Run: [Adobe Photo Downloader] "C:\Program Files\Adobe\Adobe Photoshop Lightroom 1.1\apdproxy.exe"
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\qttask.exe" -atboottime
O4 - HKLM\..\Run: [GrooveMonitor] "C:\Program Files\Microsoft Office\Office12\GrooveMonitor.exe"
O4 - HKLM\..\Run: [CTHelper] CTHELPER.EXE
O4 - HKLM\..\Run: [CTxfiHlp] CTXFIHLP.EXE
O4 - HKLM\..\Run: [StartCCC] "C:\Program Files\ATI Technologies\ATI.ACE\Core-Static\CLIStart.exe"
O4 - HKCU\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [MsnMsgr] "C:\Program Files\Windows Live\Messenger\MsnMsgr.Exe" /background
O4 - HKCU\..\Run: [swg] C:\Program Files\Google\GoogleToolbarNotifier\GoogleToolbarNotifier.exe
O4 - HKCU\..\Run: [gStart] C:\Garmin\gStart.exe
O4 - Global Startup: Reboot.exe
O4 - Global Startup: Windows Desktop Search.lnk = C:\Program Files\Windows Desktop Search\WindowsSearch.exe
O8 - Extra context menu item: &Search - http://edits.mywebsearch.com/toolbaredits/menusearch.jhtml?p=ZJ
O8 - Extra context menu item: &Windows Live Search - res://C:\Program Files\Windows Live Toolbar\msntb.dll/search.htm
O8 - Extra context menu item: Add to Windows &Live Favorites - http://favorites.live.com/quickadd.aspx
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office12\EXCEL.EXE/3000
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: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_05\bin\ssv.dll
O9 - Extra button: Send to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
O9 - Extra 'Tools' menuitem: S&end to OneNote - {2670000A-7350-4f3c-8081-5663EE0C6C49} - C:\PROGRA~1\MICROS~2\Office12\ONBttnIE.dll
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} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
O9 - Extra 'Tools' menuitem: @xpsp3res.dll,-20001 - {e2e2dd38-d088-4134-82b7-f2ba38496583} - %windir%\Network Diagnostic\xpnetdiag.exe (file missing)
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
O10 - Unknown file in Winsock LSP: c:\program files\bonjour\mdnsnsp.dll
O11 - Options group: [INTERNATIONAL] International*
O16 - DPF: {493ACF15-5CD9-4474-82A6-91670C3DD66E} (LinkedIn ContactFinderControl) - http://www.linkedin.com/cab/LinkedInContactFinderControl.cab
O18 - Protocol: grooveLocalGWS - {88FED34C-F0CA-4636-A375-3CB6248B04CD} - C:\PROGRA~1\MICROS~2\Office12\GR99D3~1.DLL
O18 - Protocol: livecall - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\WINDOW~4\MESSEN~1\MSGRAP~1.DLL
O18 - Protocol: ms-help - {314111C7-A502-11D2-BBCA-00C04F8EC294} - C:\Program Files\Common Files\Microsoft Shared\Help\hxds.dll
O18 - Protocol: msnim - {828030A1-22C1-4009-854F-8E305202313F} - C:\PROGRA~1\WINDOW~4\MESSEN~1\MSGRAP~1.DLL
O18 - Filter hijack: text/xml - {807563E5-5146-11D5-A672-00B0D022E945} - C:\PROGRA~1\COMMON~1\MICROS~1\OFFICE12\MSOXMLMF.DLL
O21 - SSODL: WPDShServiceObj - {AAA288BA-9A4C-45B0-95D7-94D524869DB5} - C:\WINDOWS\system32\WPDShServiceObj.dll
O23 - Service: Ad-Aware 2007 Service (aawservice) - Lavasoft - C:\Program Files\Lavasoft\Ad-Aware 2007\aawservice.exe
O23 - Service: Apple Mobile Device - Apple, Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\bin\AppleMobileDeviceService.exe
O23 - Service: Ati HotKey Poller - ATI Technologies Inc. - C:\WINDOWS\system32\Ati2evxx.exe
O23 - Service: ATI Smart - Unknown owner - C:\WINDOWS\system32\ati2sgag.exe
O23 - Service: AVG Anti-Spyware Guard - GRISOFT s.r.o. - C:\Program Files\Grisoft\AVG Anti-Spyware 7.5\guard.exe
O23 - Service: AVG7 Alert Manager Server (Avg7Alrt) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgamsvr.exe
O23 - Service: AVG7 Update Service (Avg7UpdSvc) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgupsvc.exe
O23 - Service: AVG E-mail Scanner (AVGEMS) - GRISOFT, s.r.o. - C:\PROGRA~1\Grisoft\AVG7\avgemc.exe
O23 - Service: ##Id_String1.6844F930_1628_4223_B5CC_5BB94B879762## (Bonjour Service) - Apple Computer, Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: Creative Service for CDROM Access - Unknown owner - C:\WINDOWS\system32\CTsvcCDA.exe (file missing)
O23 - Service: FLEXnet Licensing Service - Macrovision Europe Ltd. - C:\Program Files\Common Files\Macrovision Shared\FLEXnet Publisher\FNPLicensingService.exe
O23 - Service: Google Updater Service (gusvc) - Google - C:\Program Files\Google\Common\Google Updater\GoogleUpdaterService.exe
O23 - Service: LexBce Server (LexBceS) - Lexmark International, Inc. - C:\WINDOWS\system32\LEXBCES.EXE
O23 - Service: Nero BackItUp Scheduler 3 - Nero AG - C:\Program Files\Nero\Nero8\Nero BackItUp\NBService.exe
O23 - Service: NMIndexingService - Nero AG - C:\Program Files\Common Files\Nero\Lib\NMIndexingService.exe
O23 - Service: PLFlash DeviceIoControl Service - Prolific Technology Inc. - C:\WINDOWS\system32\IoctlSvc.exe