我一打开IE,CPU的占用率就达到100%.
HijackThis的扫描日志如下：
MSIE: Internet Explorer v6.00 SP2 (6.00.2900.2180)

Running processes:
G:\WINDOWS\System32\smss.exe
G:\WINDOWS\system32\csrss.exe
G:\WINDOWS\system32\winlogon.exe
G:\WINDOWS\system32\services.exe
G:\WINDOWS\system32\lsass.exe
G:\WINDOWS\System32\Ati2evxx.exe
G:\WINDOWS\system32\svchost.exe
G:\WINDOWS\system32\svchost.exe
G:\Program Files\Rising\Rav\CCenter.exe
G:\WINDOWS\System32\svchost.exe
G:\WINDOWS\System32\svchost.exe
G:\WINDOWS\System32\svchost.exe
G:\Program Files\Rising\Rav\Ravmond.exe
G:\WINDOWS\system32\spoolsv.exe
G:\Program Files\Rising\Rav\RavStub.exe
G:\WINDOWS\system32\drivers\CDAC11BA.EXE
G:\WINDOWS\system32\rundll32.exe
G:\WINDOWS\System32\svchost.exe
G:\WINDOWS\system32\wdfmgr.exe
G:\WINDOWS\System32\alg.exe
G:\WINDOWS\system32\Ati2evxx.exe
G:\WINDOWS\Explorer.EXE
G:\WINDOWS\system32\Rundll32.exe
G:\WINDOWS\SOUNDMAN.EXE
G:\WINDOWS\system32\atwtusb.exe
G:\Program Files\HP\HP Software Update\HPWuSchd2.exe
G:\Program Files\HP\hpcoretech\hpcmpmgr.exe
G:\Program Files\Common Files\Real\Update_OB\realsched.exe
G:\PROGRA~1\3721\assistse.exe
G:\Program Files\3721\Dlaccel\YDownloader.exe
G:\WINDOWS\system32\rundll32.exe
G:\Program Files\Rising\Rav\RavTask.exe
G:\WINDOWS\system32\ctfmon.exe
G:\WINDOWS\system32\DrvMon.exe
G:\Program Files\Rising\Rav\Ravmon.exe
G:\Program Files\InterVideo\Common\Bin\WinCinemaMgr.exe
G:\Program Files\Tencent\QQ\QQ.exe
G:\Program Files\HP\Digital Imaging\bin\hpqgalry.exe
G:\Program Files\Tencent\QQ\TIMPlatform.exe
G:\Program Files\HP\hpcoretech\comp\hptskmgr.exe
G:\Program Files\Internet Explorer\iexplore.exe
G:\WINDOWS\system32\rundll32.exe
G:\Program Files\Internet Explorer\iexplore.exe
G:\Program Files\Tencent\QQ\HDRoom.exe
G:\Documents and Settings\All Users\Documents\248783200522382732\HijackThis.exe

R3 - URLSearchHook: 上网助手 - {BB936323-19FA-4521-BA29-ECA6A121BC78} - G:\PROGRA~1\3721\Assist\asbar.dll
O2 - BHO: ThunderIEHelper Class - {0005A87D-D626-4B3A-84F9-1D9571695F55} - G:\WINDOWS\system32\xunleibho_v5.dll
O2 - BHO: AcroIEHlprObj Class - {06849E9F-C8D7-4D59-B87D-784B7D6BE0B3} - G:\Program Files\Adobe\Acrobat 7.0\ActiveX\AcroIEHelper.dll
O2 - BHO: (no name) - {2F401A09-2F10-455E-A15D-4C8B9D8D7AEB} - G:\PROGRA~1\黄河FL~1\hhcatch.dll
O2 - BHO: Anti Fish - {38928D50-8A48-44C2-945F-D2F23F771410} - G:\Program Files\3721\Assist\Angling.dll
O2 - BHO: QQBrowserHelperObject Class - {54EBD53A-9BC1-480B-966A-843A333CA162} - G:\Program Files\Tencent\QQ\QQIEHelper.dll
O2 - BHO: MMSAssist - {6671A431-5C3D-463d-A7CF-5587F9B7E191} - G:\PROGRA~1\MMSASS~1\MMSASS~1.DLL
O2 - BHO: std software - {6A512BF7-EC78-4e8d-9841-6C02E8FA9838} - G:\WINDOWS\SYSTEM32\stdup.dll
O2 - BHO: IeCatch2 Class - {A5366673-E8CA-11D3-9CD9-0090271D075B} - G:\PROGRA~1\FLASHGET\jccatch.dll
O2 - BHO: (no name) - {A9930D97-9CF0-42A0-A10D-4F28836579D5} - G:\PROGRA~1\KuGoo2\KUGOO3~1.OCX
O2 - BHO: Google Toolbar Helper - {AA58ED58-01DD-4d91-8333-CF10577473F7} - g:\program files\google\googletoolbar1.dll
O2 - BHO: 上网助手 - {BB936323-19FA-4521-BA29-ECA6A121BC78} - G:\PROGRA~1\3721\Assist\asbar.dll
O2 - BHO: IE - {D157330A-9EF3-49F8-9A67-4141AC41ADD4} - G:\WINDOWS\downlo~1\CnsHook.dll
O3 - Toolbar: FlashGet Bar - {E0E899AB-F487-11D5-8D29-0050BA6940E3} - G:\PROGRA~1\FLASHGET\fgiebar.dll
O3 - Toolbar: 上网助手 - {BB936323-19FA-4521-BA29-ECA6A121BC78} - G:\PROGRA~1\3721\Assist\asbar.dll
O3 - Toolbar: (no name) - {6C3797D2-3FEF-4cd4-B654-D3AE55B4128C} - (no file)
O3 - Toolbar: 完美网译通 - {F43BD772-ABDD-43b7-A96A-3E9E61946EC0} - G:\WINDOWS\WORLD2\TOOLBAR\hmtoolbar.dll
O3 - Toolbar: &Google - {2318C2B1-4965-11d4-9B18-009027A5CD4F} - g:\program files\google\googletoolbar1.dll
O4 - HKLM\..\Run: [IMJPMIG8.1] "G:\WINDOWS\IME\imjp8_1\IMJPMIG.EXE" /Spoil /RemAdvDef /Migration32
O4 - HKLM\..\Run: [PHIME2002ASync] G:\WINDOWS\System32\IME\TINTLGNT\TINTSETP.EXE /SYNC
O4 - HKLM\..\Run: [PHIME2002A] G:\WINDOWS\System32\IME\TINTLGNT\TINTSETP.EXE /IMEName
O4 - HKLM\..\Run: [ATIPTA] rem G:\Program Files\ATI Technologies\ATI Control Panel\atiptaxx.exe
O4 - HKLM\..\Run: [SoundMan] SOUNDMAN.EXE
O4 - HKLM\..\Run: [atwtusb] atwtusb.exe beta
O4 - HKLM\..\Run: [IMSCMig] rem G:\PROGRA~1\COMMON~1\MICROS~1\IME\IMSC40A\IMSCMIG.EXE /Preload
O4 - HKLM\..\Run: [HP Software Update] "G:\Program Files\HP\HP Software Update\HPWuSchd2.exe"
O4 - HKLM\..\Run: [HP Component Manager] "G:\Program Files\HP\hpcoretech\hpcmpmgr.exe"
O4 - HKLM\..\Run: [TkBellExe] "G:\Program Files\Common Files\Real\Update_OB\realsched.exe"  -osboot
O4 - HKLM\..\Run: [assistse] "G:\PROGRA~1\3721\assistse.exe"
O4 - HKLM\..\Run: [CnsMin] Rundll32.exe G:\WINDOWS\downlo~1\CnsMin.dll,Rundll32
O4 - HKLM\..\Run: [yahoo_mini] G:\Program Files\3721\Dlaccel\YDownloader.exe
O4 - HKLM\..\Run: [NMGameX_AutoRun] G:\WINDOWS\system32\Rundll32.exe NMGameX.dll,LiveProcess /aa
O4 - HKLM\..\Run: [helper.dll] G:\WINDOWS\system32\rundll32.exe G:\PROGRA~1\3721\helper.dll,Rundll32
O4 - HKLM\..\Run: [RavTask] "G:\Program Files\Rising\Rav\RavTask.exe" -system
O4 - HKCU\..\Run: [ctfmon.exe] G:\WINDOWS\system32\ctfmon.exe
O4 - HKCU\..\Run: [Skype] rem "d:\Program Files\Skype\Phone\Skype.exe" /nosplash /minimized
O4 - HKCU\..\Run: [DrvMon.exe] G:\WINDOWS\system32\DrvMon.exe
O4 - Startup: 腾讯QQ.lnk = G:\Program Files\Tencent\QQ\QQ.exe
O4 - Startup: start.lnk = ?
O4 - Global Startup: InterVideo WinCinema Manager.lnk = G:\Program Files\InterVideo\Common\Bin\WinCinemaMgr.exe
O4 - Global Startup: HP Image Zone 快速启动 .lnk = G:\Program Files\HP\Digital Imaging\bin\hpqthb08.exe
O4 - Global Startup: HP Digital Imaging Monitor.lnk = G:\Program Files\HP\Digital Imaging\bin\hpqtra08.exe
O4 - Global Startup: Adobe Reader Speed Launch.lnk = G:\Program Files\Adobe\Acrobat 7.0\Reader\reader_sl.exe

建议楼主把3721删除了

O8 - Extra context menu item:  >> 彩信发送 << - res://G:\PROGRA~1\MMSASS~1\MMSASS~1.DLL/mms.htm
O8 - Extra context menu item: &Google Search - res://g:\program files\google\GoogleToolbar2.dll/cmsearch.html
O8 - Extra context menu item: &使用下载加速专家下载 - G:\Program Files\3721\Dlaccel\geturl.htm
O8 - Extra context menu item: &使用迅雷下载 - G:\Program Files\Sandai Technologies Inc\Thunder\geturl.htm
O8 - Extra context menu item: &使用迅雷下载全部链接 - G:\Program Files\Sandai Technologies Inc\Thunder\getAllurl.htm
O8 - Extra context menu item: Backward Links - res://g:\program files\google\GoogleToolbar2.dll/cmbacklinks.html
O8 - Extra context menu item: Cached Snapshot of Page - res://g:\program files\google\GoogleToolbar2.dll/cmcache.html
O8 - Extra context menu item: Similar Pages - res://g:\program files\google\GoogleToolbar2.dll/cmsimilar.html
O8 - Extra context menu item: Translate into English - res://g:\program files\google\GoogleToolbar2.dll/cmtrans.html
O8 - Extra context menu item: 使用KuGoo3下载(&K) - G:\PROGRA~1\KUGOO2\KuGoo3DownX.htm
O8 - Extra context menu item: 使用网际快车下载 - G:\Program Files\FlashGet\jc_link.htm
O8 - Extra context menu item: 使用网际快车下载全部链接 - G:\Program Files\FlashGet\jc_all.htm
O8 - Extra context menu item: 导出到 Microsoft Office Excel(&X) - res://G:\PROGRA~1\MICROS~2\OFFICE11\EXCEL.EXE/3000
O8 - Extra context menu item: 导出当前页到超星阅览器(&A) - G:\Program Files\SSREADER36\ss_all.htm
O8 - Extra context menu item: 导出选中部分到超星阅览器(&S) - G:\Program Files\SSREADER36\ss_select.htm
O8 - Extra context menu item: 添加到QQ自定义面板 - G:\Program Files\Tencent\QQ\AddPanel.htm
O8 - Extra context menu item: 添加到QQ表情 - G:\Program Files\Tencent\QQ\AddEmotion.htm
O8 - Extra context menu item: 用QQ彩信发送该图片 - G:\Program Files\Tencent\QQ\SendMMS.htm
O8 - Extra context menu item: 百度-搜索MP3 - res://G:\Progra~1\Baidu\bar\BaiDuBar.dll/BAIDUMP3.HTM
O8 - Extra context menu item: 百度-搜索图片 - res://G:\Progra~1\Baidu\bar\BaiDuBar.dll/BAIDUIMG.HTM
O8 - Extra context menu item: 百度-搜索新闻 - res://G:\Progra~1\Baidu\bar\BaiDuBar.dll/BAIDUNEWS.HTM
O8 - Extra context menu item: 百度-搜索歌词 - res://G:\Progra~1\Baidu\bar\BaiDuBar.dll/BAIDULYRIC.HTM
O8 - Extra context menu item: 百度-搜索网页 - res://G:\Progra~1\Baidu\bar\BaiDuBar.dll/BAIDUSEARCH.HTM
O8 - Extra context menu item: 百度-搜索贴吧 - res://G:\Progra~1\Baidu\bar\BaiDuBar.dll/BAIDUPOST.HTM
O8 - Extra context menu item: 百度-词典搜索 - res://G:\Progra~1\Baidu\bar\BaiDuBar.dll/BAIDU_DIC.HTM
O8 - Extra context menu item: 黄河&Flash播放器 - G:\PROGRA~1\黄河FL~1\geturl.htm
O9 - Extra button: 手机短信 - {00000000-0000-0001-0001-596BAEDD1289} - http://sms.3721.com/ie/index.htm?pid=U_3721_assist (file missing)
O9 - Extra button: 铃声 - {0713E8D2-850A-101B-AFC0-4210102A8DA7} - http://huanghetv.sms.163.com (file missing)
O9 - Extra button: 浩方对战平台 - {0A155D3C-68E2-4215-A47A-E800A446447A} - F:\[赛博思集团].files\cs1.5\浩方对战平台\浩方对战平台\GameClient.exe (file missing)
O9 - Extra button: Yahoo 1G电邮 - {507F9113-CD77-4866-BA92-0E86DA3D0B97} - http://cn.mail.yahoo.com/promo/rd1 (file missing)
O9 - Extra button: 寻宝乐趣多 - {59BC54A2-56B3-44a0-93E5-432D58746E26} - http://hot.3721.com/rd/shop_btn.htm (file missing)
O9 - Extra button: 上网助手 - {5D73EE86-05F1-49ed-B850-E423120EC338} - http://assistant.3721.com/index.htm?fb=Cns (file missing)
O9 - Extra button: (no name) - {6671A433-5C3D-463d-A7CF-5587F9B7E191} - G:\PROGRA~1\MMSASS~1\MMSASS~1.DLL
O9 - Extra 'Tools' menuitem: MMSAssist工具条设置 - {6671A433-5C3D-463d-A7CF-5587F9B7E191} - G:\PROGRA~1\MMSASS~1\MMSASS~1.DLL
O9 - Extra button: 信息检索 - {92780B25-18CC-41C8-B9BE-3C9C571A8263} - G:\PROGRA~1\MICROS~2\OFFICE11\REFIEBAR.DLL
O9 - Extra button: QQ - {c95fe080-8f5d-11d2-a20b-00aa003c157b} - G:\Program Files\Tencent\QQ\QQ.EXE
O9 - Extra 'Tools' menuitem: 腾讯QQ - {c95fe080-8f5d-11d2-a20b-00aa003c157b} - G:\Program Files\Tencent\QQ\QQ.EXE
O9 - Extra button: FlashGet - {D6E814A0-E0C5-11d4-8D29-0050BA6940E3} - G:\PROGRA~1\FLASHGET\flashget.exe
O9 - Extra 'Tools' menuitem: &FlashGet - {D6E814A0-E0C5-11d4-8D29-0050BA6940E3} - G:\PROGRA~1\FLASHGET\flashget.exe
O9 - Extra button: (no name) - {DEDEB80D-FA35-45d9-9460-4983E5A8AFE6} - G:\Program Files\Tencent\QQ\QQIEHelper.dll
O9 - Extra 'Tools' menuitem: QQ炫彩工具条设置 - {DEDEB80D-FA35-45d9-9460-4983E5A8AFE6} - G:\Program Files\Tencent\QQ\QQIEHelper.dll
O9 - Extra button: 情景聊天 - {E5D12C4E-7B4F-11D3-B5C9-0050045C3C96} - http://cn.rd.yahoo.com/home/messenger/bjk/clientbtn/?http://cn.messenger.yahoo.com/ (file missing)
O9 - Extra button: (no name) - {ECF2E268-F28C-48d2-9AB7-8F69C11CCB71} - http://assistant.3721.com/security1.htm?fb=Cns (file missing)
O9 - Extra 'Tools' menuitem: 修复浏览器 - {ECF2E268-F28C-48d2-9AB7-8F69C11CCB71} - http://assistant.3721.com/security1.htm?fb=Cns (file missing)
O9 - Extra button: Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - G:\Program Files\Messenger\msmsgs.exe
O9 - Extra 'Tools' menuitem: Windows Messenger - {FB5F1910-F110-11d2-BB9E-00C04F795683} - G:\Program Files\Messenger\msmsgs.exe
O9 - Extra button: (no name) - {FD00D911-7529-4084-9946-A29F1BDF4FE5} - http://assistant.3721.com/clean1.htm?fb=Cns (file missing)
O9 - Extra 'Tools' menuitem: 清理上网记录 - {FD00D911-7529-4084-9946-A29F1BDF4FE5} - http://assistant.3721.com/clean1.htm?fb=Cns (file missing)
O11 - Options group: [!CNS]  上网助手-地址栏搜索
O12 - Plugin for .MID: G:\Program Files\Internet Explorer\PLUGINS\npqtplugin2.dll
O16 - DPF: {2354A44B-3CEB-4829-9940-545B03103538} (PowerPlr Control) - http://bbsky.wuhan.net.cn/plugin/PowerPlr.ocx
O16 - DPF: {3D8F74EE-8692-4F8F-B8D2-7522E732519E} (WebActivater Control) - http://game.qq.com/QQGame2.cab
O16 - DPF: {DF6FE46D-1D23-4668-AD3A-CDEA1262B282} (PowerDld Control) - http://bbsky.wuhan.net.cn/plugin/PowerDld.ocx
O16 - DPF: {E4E2F180-CB8B-4DE9-ACBB-DA745D3BA153} (Rising Web Scan Object) - http://download.rising.com.cn/register/pcver/autoupgradepad/pcver2006new/OL2006.cab
O17 - HKLM\System\CCS\Services\Tcpip\..\{C103967B-B567-4F8C-8BA5-85E2C37EA2A7}: NameServer = 202.103.0.68,202.103.24.68
O18 - Protocol: koboo - {7DEE9D05-FA0A-4416-A6F3-6537D0EAB6A6} - G:\WINDOWS\system32\mbprot.dll
O23 - Service: Ati HotKey Poller - Unknown owner - G:\WINDOWS\System32\Ati2evxx.exe
O23 - Service: ATI Smart - Unknown owner - G:\WINDOWS\system32\ati2sgag.exe
O23 - Service: C-DillaCdaC11BA - Macrovision - G:\WINDOWS\system32\drivers\CDAC11BA.EXE
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - G:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: Macromedia Licensing Service - Unknown owner - G:\Program Files\Common Files\Macromedia Shared\Service\Macromedia Licensing.exe
O23 - Service: Remote Packet Capture Protocol v.0 (experimental) (rpcapd) - Unknown owner - %ProgramFiles%\WinPcap\rpcapd.exe" -d -f "%ProgramFiles%\WinPcap\rpcapd.ini (file missing)
O23 - Service: Rising Process Communication Center (RsCCenter) - Beijing Rising Technology Co., Ltd. - G:\Program Files\Rising\Rav\CCenter.exe
O23 - Service: RsRavMon Service (RsRavMon) - Beijing Rising Technology Co., Ltd. - G:\Program Files\Rising\Rav\Ravmond.exe