Ciao a tutti ho il pc da due gg che ha la cpu al 100% dopo averlo acceso senza programmi aperti.VI allego il log di hijackthis:
Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 20.00.41, on 13/12/2013
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
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:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\Avira\AntiVir Desktop\sched.exe
C:\Programmi\Avira\AntiVir Desktop\avguard.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\wuauclt.exe
C:\WINDOWS\Explorer.EXE
C:\Programmi\Avira\AntiVir Desktop\avgnt.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Avira\AntiVir Desktop\avshadow.exe
C:\WINDOWS\system32\wuauclt.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Programmi\Trend Micro\HiJackThis\HiJackThis.exe
C:\Programmi\Internet Explorer\IEXPLORE.EXE
C:\WINDOWS\SoftwareDistribution\Download\4af00d15580f3fc3068bdd06c942dddc\update\update.exe
C:\WINDOWS\system32\rundll32.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
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://www.bigseekpro.com/splitcam/{3DDF777A-B269-4BEA-9473-325B9AA5E54C}
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
R3 - URLSearchHook: uTorrentBar_IT Toolbar - {4ae0c3d6-f713-4eed-bc65-25dc3ffdaac1} - C:\Programmi\uTorrentBar_IT\prxtbuTo0.dll
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 5.0\Reader\ActiveX\AcroIEHelper.ocx
O2 - BHO: uTorrentBar_IT - {4ae0c3d6-f713-4eed-bc65-25dc3ffdaac1} - C:\Programmi\uTorrentBar_IT\prxtbuTo0.dll
O2 - BHO: Guida per l'accesso a Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O3 - Toolbar: uTorrentBar_IT Toolbar - {4ae0c3d6-f713-4eed-bc65-25dc3ffdaac1} - C:\Programmi\uTorrentBar_IT\prxtbuTo0.dll
O4 - HKLM\..\Run: [avgnt] "C:\Programmi\Avira\AntiVir Desktop\avgnt.exe" /min
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'Default user')
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
O10 - Unknown file in Winsock LSP: c:\windows\system32\nvlsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\nvlsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\nvlsp.dll
O10 - Unknown file in Winsock LSP: c:\windows\system32\nvlsp.dll
O12 - Plugin for .spop: C:\Programmi\Internet Explorer\Plugins\NPDocBox.dll
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\Skype4COM.dll
O22 - SharedTaskScheduler: Precaricatore Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Daemon di cache delle categorie di componenti - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: Avira Pianificatore (AntiVirSchedulerService) - Avira Operations GmbH & Co. KG - C:\Programmi\Avira\AntiVir Desktop\sched.exe
O23 - Service: Avira Real-Time Protection (AntiVirService) - Avira Operations GmbH & Co. KG - C:\Programmi\Avira\AntiVir Desktop\avguard.exe
O23 - Service: Skype Updater (SkypeUpdate) - Skype Technologies - C:\Programmi\Skype\Updater\Updater.exe

--
End of file - 4377 bytes

Hai un infezione da bigseekpro.com è un dirottatore e ti ha modificato anche la pagina iniziale del browser, controlla la home page se è modificata e sostituiscila con la tua preferita, poi controlla fra i motori di ricerca se c'è bigseekpro.com lo rimuovi, controlla anche nel pannello di controllo, installazione applicazioni se trovi quel programma, se c'è lo rimuovi.

Poi fai queste scansioni nell'ordine, leggi bene le indicazioni:

Scarica ed installa MalwareBytes:
clicca qui per il download : http://www.aiutamici.com/software?id=80346
Clicca su: Link al sito principale, poi nella pagina che appare clicca su: Free Version Download.
Prima di fare la scansione AGGIORNALO. (è molto importante)
Esegui una scansione completa del sistema. (NON veloce)
Elimina gli eventuali file infetti trovati. (li devi selezionare, e poi cliccare su "Rimuovi selezionati")
Posta il log.

Scarica Adwcleaner sul desktop:
http://general-changelog-team.fr/fr/downloads/finish/20-outils-de-xplode/2-adwcleaner
Chiudi tutti i browser (è importante IE,Firefox Chrome ecc...)
Clicca sul pulsante "Scan".
Finita la scansione clicca su "Clean"
Conferma con OK le varie finestre che ti compariranno.
Il pc si riavvierà, e uscirà il log con le eliminazioni.
Postalo qui.

Scarica Junkware Removal Tool sul desktop.
http://www.majorgeeks.com/mg/get/junkware_removal_tool,1.html
Disattiva temporaneamente l'antivirus per evitare potenziali conflitti.
Doppio click su JRT
Lo strumento si aprirà e avvierà la scansione del sistema.
Devi avere pazienza in quanto questo tool può richiedere del tempo per completare la scansione .
Al termine, un log (JRT.txt) viene salvato sul desktop e si aprirà automaticamente.
Postalo qui.
Tutte le scansioni vanno fatte in modalità NORMALE.

Poi fai una pulizia con Ccleaner compreso il Registro, per il Registro spunta tutte le voci, acconsenti al backup quando richiesto, sempre in Ccleaner vai in Strumenti Ripristino Sistema seleziona tutte le voci tranne l'ultima che non è selezionabile e rimane per sicurezza, poi clic su Rimuovi.
Se non conosci il programma, lo trovi su Aiutamici sezione software.

Alla fine rifai una scansione con HJT e posta il log aggiornato, vediamo se c'è qualche voce da rimuovere.
Ciao

# AdwCleaner v3.015 - Report created 14/12/2013 at 14:09:05
# Updated 10/12/2013 by Xplode
# Operating System : Microsoft Windows XP Service Pack 3 (32 bits)
# Username : Pomata - ICE
# Running from : C:\Documents and Settings\Pomata\Desktop\adwcleaner.exe
# Option : Clean

***** [ Services ] *****


***** [ Files / Folders ] *****

Folder Deleted : C:\Documents and Settings\All Users\Dati applicazioni\Conduit
Folder Deleted : C:\Programmi\Conduit
Folder Deleted : C:\Programmi\uTorrentBar_IT
Folder Deleted : C:\Documents and Settings\Pomata\Impostazioni locali\Dati applicazioni\Conduit
Folder Deleted : C:\Documents and Settings\Pomata\Impostazioni locali\Dati applicazioni\uTorrentBar_IT

***** [ Shortcuts ] *****


***** [ Registry ] *****

Key Deleted : HKCU\Toolbar
Key Deleted : HKLM\SOFTWARE\Classes\Toolbar.CT2851640
Key Deleted : HKLM\SOFTWARE\Classes\CLSID\{3C471948-F874-49F5-B338-4F214A2EE0B1}
Key Deleted : HKLM\SOFTWARE\Classes\CLSID\{4AE0C3D6-F713-4EED-BC65-25DC3FFDAAC1}
Key Deleted : HKLM\SOFTWARE\Classes\CLSID\{854145C6-B95A-408D-BE86-367DC393A219}
Key Deleted : HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\Browser Helper Objects\{4AE0C3D6-F713-4EED-BC65-25DC3FFDAAC1}
Key Deleted : HKCU\Software\Microsoft\Windows\CurrentVersion\Ext\Stats\{AE805869-2E5C-4ED4-8F7B-F1F7851A4497}
Key Deleted : HKCU\Software\Microsoft\Windows\CurrentVersion\Ext\Stats\{FCBCCB87-9224-4B8D-B117-F56D924BEB18}
Key Deleted : HKCU\Software\Microsoft\Windows\CurrentVersion\Ext\Stats\{4AE0C3D6-F713-4EED-BC65-25DC3FFDAAC1}
Key Deleted : HKCU\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{AE805869-2E5C-4ED4-8F7B-F1F7851A4497}
Key Deleted : HKCU\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{FCBCCB87-9224-4B8D-B117-F56D924BEB18}
Key Deleted : HKCU\Software\Microsoft\Windows\CurrentVersion\Ext\Settings\{4AE0C3D6-F713-4EED-BC65-25DC3FFDAAC1}
Key Deleted : HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Ext\PreApproved\{854145C6-B95A-408D-BE86-367DC393A219}
Key Deleted : HKLM\SOFTWARE\Microsoft\Internet Explorer\Low Rights\ElevationPolicy\{A25E3E84-3A5C-49D3-BF3A-6A68AD0156D3}
Key Deleted : HKLM\SOFTWARE\Microsoft\Internet Explorer\Low Rights\ElevationPolicy\{2C5E4373-6571-45E1-81C3-0E9D71F73D6E}
Key Deleted : HKCU\Software\Microsoft\Internet Explorer\SearchScopes\{AFDBDDAA-5D3F-42EE-B79C-185A7020515B}
Value Deleted : HKLM\SOFTWARE\Microsoft\Internet Explorer\Toolbar [{4AE0C3D6-F713-4EED-BC65-25DC3FFDAAC1}]
Value Deleted : HKCU\Software\Microsoft\Internet Explorer\Toolbar\WebBrowser [{4AE0C3D6-F713-4EED-BC65-25DC3FFDAAC1}]
Key Deleted : HKCU\Software\APN PIP
Key Deleted : HKCU\Software\Conduit
Key Deleted : HKCU\Software\Iminent
Key Deleted : HKCU\Software\SmartBar
Key Deleted : HKCU\Software\Softonic
Key Deleted : HKCU\Software\uTorrentBar_IT
Key Deleted : HKLM\Software\Conduit
Key Deleted : HKLM\Software\Iminent
Key Deleted : HKLM\Software\PIP
Key Deleted : HKLM\Software\uTorrentBar_IT
Key Deleted : HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\SearchTheWebARP
Key Deleted : HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Uninstall\uTorrentBar_IT Toolbar
Key Deleted : HKLM\Software\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\0238BBE24EA3A70408B81E4BB89C15E5
Key Deleted : HKLM\Software\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\0FF2AEFF45EEA0A48A4B33C1973B6094
Key Deleted : HKLM\Software\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\29799DE249E7DBC459FC6C8F07EB8375
Key Deleted : HKLM\Software\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\305B09CE8C53A214DB58887F62F25536
Key Deleted : HKLM\Software\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\43C098337DB065A49B665D4EA7F16D1C
Key Deleted : HKLM\Software\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\A71991503412AEB42838B02C5ED9F9CD
Key Deleted : HKLM\Software\Microsoft\Windows\CurrentVersion\Installer\UserData\S-1-5-18\Components\F7652513C62FF63448CFF05163719DB7

***** [ Browsers ] *****

-\\ Internet Explorer v8.0.6001.18702


*************************

AdwCleaner[R0].txt - [4260 octets] - [14/12/2013 14:07:38]
AdwCleaner[S0].txt - [4275 octets] - [14/12/2013 14:09:05]

########## EOF - C:\AdwCleaner\AdwCleaner[S0].txt - [4335 octets] ##########

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 17.01.48, on 14/12/2013
Platform: Windows XP SP3 (WinNT 5.01.2600)
MSIE: Internet Explorer v8.00 (8.00.6001.18702)
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:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Programmi\Avira\AntiVir Desktop\sched.exe
C:\Programmi\Avira\AntiVir Desktop\avguard.exe
C:\Programmi\Malwarebytes' Anti-Malware\mbamscheduler.exe
C:\WINDOWS\system32\svchost.exe
C:\Programmi\Avira\AntiVir Desktop\avgnt.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Programmi\Avira\AntiVir Desktop\avshadow.exe
C:\WINDOWS\system32\wuauclt.exe
C:\WINDOWS\explorer.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\system32\wuauclt.exe
C:\Programmi\Internet Explorer\IEXPLORE.EXE
C:\Programmi\Internet Explorer\IEXPLORE.EXE
C:\Programmi\Trend Micro\HiJackThis\HiJackThis.exe

R0 - HKCU\Software\Microsoft\Internet Explorer\Main,Start Page = http://www.google.it/
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
R0 - HKCU\Software\Microsoft\Internet Explorer\Toolbar,LinksFolderName = Collegamenti
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - C:\Programmi\Adobe\Acrobat 5.0\Reader\ActiveX\AcroIEHelper.ocx
O2 - BHO: Guida per l'accesso a Windows Live - {9030D464-4C02-4ABF-8ECC-5164760863C6} - C:\Programmi\File comuni\Microsoft Shared\Windows Live\WindowsLiveLogin.dll
O4 - HKLM\..\Run: [avgnt] "C:\Programmi\Avira\AntiVir Desktop\avgnt.exe" /min
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - HKUS\S-1-5-18\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'SYSTEM')
O4 - HKUS\S-1-5-18\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'SYSTEM')
O4 - HKUS\.DEFAULT\..\Run: [CTFMON.EXE] C:\WINDOWS\system32\CTFMON.EXE (User 'Default user')
O4 - HKUS\.DEFAULT\..\RunOnce: [_nltide_3] rundll32 advpack.dll,LaunchINFSectionEx nLite.inf,C,,4,N (User 'Default user')
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
O18 - Protocol: skype4com - {FFC8B962-9B40-4DFF-9458-1830C7DD7F5D} - C:\PROGRA~1\FILECO~1\Skype\Skype4COM.dll
O22 - SharedTaskScheduler: Precaricatore Browseui - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\system32\browseui.dll
O22 - SharedTaskScheduler: Daemon di cache delle categorie di componenti - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\system32\browseui.dll
O23 - Service: Avira Pianificatore (AntiVirSchedulerService) - Avira Operations GmbH & Co. KG - C:\Programmi\Avira\AntiVir Desktop\sched.exe
O23 - Service: Avira Real-Time Protection (AntiVirService) - Avira Operations GmbH & Co. KG - C:\Programmi\Avira\AntiVir Desktop\avguard.exe
O23 - Service: MBAMScheduler - Malwarebytes Corporation - C:\Programmi\Malwarebytes' Anti-Malware\mbamscheduler.exe
O23 - Service: MBAMService - Malwarebytes Corporation - C:\Programmi\Malwarebytes' Anti-Malware\mbamservice.exe
O23 - Service: Skype Updater (SkypeUpdate) - Skype Technologies - C:\Programmi\Skype\Updater\Updater.exe

--
End of file - 3851 bytes

Ok adesso provo per ora grazie 1000!!!!