changing graphics settings causes freeze

So... I just upgraded to a GTX570 (I have the best Dad ever), and was looking forward to cranking the graphics settings way up on CoH. Problem is, if I try to move the shadow sliders or the ambient occlusion sliders at all the program freezes and I have to go into task manager and end process. Oddly, I can turn up most of the other graphics settings and sliders without noticing any change in performance or anything, though I don't think I've checked every setting. I tried uninstalling and reinstalling drivers, tried the beta drivers for the card, ran Driver Sweeper and reinstalled the latest drivers, and still no luck. I'm not running Riva Tuner or EVGA Precision or anything like that, and I've tried closing out all the background processes I can get away with to no avail. So here's my CoH Helper dump:

---System information gathered by CoH Helper version 0.2.0.2---

DxDiag gathered at March 8, 2011 18:34 (-08:00)
Operating System: Windows XP Professional (5.1, Build 2600) Service Pack 3 (2600.xpsp_sp3_gdr.101209-1647)
System Manufacturer: System manufacturer
System Model: System Product Name
BIOS: Phoenix - AwardBIOS v6.00PG
Central Processor: AMD Athlon(tm) 64 X2 Dual Core Processor 5600+, MMX, 3DNow (2 CPUs), ~2.8GHz
Memory: 2046MB
.Net Memory Report: 1377MB out of 2046MB available
Page File: 3471MB (466MB currently in use)
C Drive: (Maxtor 6H500F0) 1012MB out of 32765MB (3%) free
E Drive: (Maxtor 6H500F0) 176270MB out of 222086MB (79%) free
F Drive: (Maxtor 6H500F0) 161360MB out of 222086MB (72%) free
D Drive: (LITE-ON DVDRW LH-20A1P) zero-size drive
J Drive: (LZ3718Y FBO353H SCSI CdRom Device) zero-size drive
Windows directory location: C:\WINDOWS
DirectX: DirectX 9.0c (4.09.0000.0904)
DirectX Diag version: 5.03.2600.5512 (32-bit version)

Display Notes: No problems found.
Sound Notes: No problems found.
Input Notes: No problems found.

Monitor: Dell 2000FP(Digital)
Monitor's Max Resolution: 1600,1200
Video Device Name: NVIDIA GeForce GTX 570
Manufacturer / Chip: NVIDIA / GeForce GTX 570
Video Memory: 1280.0 MB
Driver Version: 6.14.0012.6658
Driver Date: 1/7/2011 7:27:00 PM
Driver Language: English

Sound Device Description: SoundMAX HD Audio
Driver File: ADIHdAud.sys
Driver Version: 5.10.0001.4580
Driver Date: 9/8/2006 5:08:06 PM


WMI Information
Motherboard Manufacturer: ASUSTeK Computer INC.
Motherboard Model: (empty)
Motherboard Product: M2N32-SLI DELUXE
Motherboard Version: 1.XX
BIOS Manufacturer: Phoenix Technologies, LTD
BIOS Name: Phoenix - AwardBIOS v6.00PG
BIOS Version: Nvidia - 42302e31
BIOS Release: 20070102000000.000000+000


Registry Information for Current User
Resolution: 1600x1200
3D Resolution: 1600x1200 (Not using renderscale)
Full Screen: Yes
Maximized: No
Screen Position: 0, 0
Refresh Rate: 60Hz
Vertical Sync Enabled: Yes


Physics Quality: High
Maximum Particles: 27081
Max Particle Fill? 10.000
Physics Card Enabled: No


Anti-aliasing: 4x
Anisotropic Filtering: 16x
Texture LOD Bias: Smooth
Water Effects: Ultra quality
Bloom: 1.000 (turned on)
Depth of Field Enabled: Yes
Desaturation Effects (Sepia) Enabled: Yes
Shader Detail: High


World Texture Level: Very High
Character Texture Level: High
World Detail Level (Vis_Scale): 2.000
Entity Detail Level: 2.000
Shadows Enabled: Yes
Shadow Mode: Stencil shadows
Shadow Map Shader: Unknown (0)
Environmental Reflections: Ultra quality
Advanced Occlusion Settings: No
Ambient Occlusion: Off
Occlusion Strength: Off
Blur: Bilateral
Ambient Resolution: Performance


Gamma Correction: 1.000
Geometry Buffers (VBOs) Enabled: Yes
Suppression of FX When Camera Close Enabled: No
Close Suppression Range: 3.000
Show Advertisements: Yes

Audio Mode: Compatiblity
3D Audio: Yes
FX Sound Volume: 0.215
Music Sound Volume: 0.221

Show Advanced Graphics Options: Yes
Overall Graphics Quality: 0.500
Reverse Mouse Buttons: No
Save Login Username: Yes
Transfer Rate: 235959 bytes/second
Current Game Version: 1950.201102230015.1
Installation Directory: C:\Program Files\City of Heroes

Mod files in the Data directory
.\texture_library\GUI\Icons\Powers has 64 files
.\texture_library\MAPS\city has 1 file
.\texture_library\MAPS\Midnight_Squad has 1 file
.\texture_library\MAPS\Safeguard has 9 files
.\texture_library\MAPS\sewers has 44 files
.\texture_library\MAPS\static has 34 files
.\texture_library\V_MAPS\Outdoor_Missions has 9 files
.\texture_library\V_MAPS\Static has 16 files

And the Hijack This log...

Logfile of Trend Micro HijackThis v2.0.4
Scan saved at 7:25:34 PM, on 3/8/2011
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\nvsvc32.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\system32\spoolsv.exe
C:\Program Files\Common Files\Apple\Mobile Device Support\AppleMobileDeviceService.exe
C:\Program Files\Bonjour\mDNSResponder.exe
C:\WINDOWS\system32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\System32\svchost.exe
C:\WINDOWS\Explorer.EXE
C:\Program Files\Analog Devices\Core\smax4pnp.exe
C:\Program Files\Analog Devices\SoundMAX\Smax4.exe
C:\WINDOWS\Logi_MwX.Exe
C:\WINDOWS\system32\spool\drivers\w32x86\3\hpztsb0 7.exe
C:\Program Files\HP\HP Software Update\HPWuSchd2.exe
E:\Program Files\iTunes\iTunesHelper.exe
C:\WINDOWS\system32\RUNDLL32.EXE
E:\Program Files\DAEMON Tools\daemon.exe
C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
C:\WINDOWS\system32\ctfmon.exe
C:\Program Files\HP\Digital Imaging\bin\hpqtra08.exe
C:\Program Files\Logitech\SetPoint\SetPoint.exe
C:\Program Files\Common Files\Logishrd\KHAL2\KHALMNPR.EXE
C:\WINDOWS\system32\wuauclt.exe
C:\Program Files\iPod\bin\iPodService.exe
C:\WINDOWS\system32\wscntfy.exe
C:\Program Files\HP\Digital Imaging\bin\hpqSTE08.exe
C:\Program Files\HP\Digital Imaging\bin\hpqbam08.exe
C:\Program Files\Mozilla Firefox\firefox.exe
C:\Documents and Settings\Alyssa\Desktop\HijackThis.exe

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\Int ernet Settings,ProxyOverride = *.local
O2 - BHO: HP Print Enhancer - {0347C33E-8762-4905-BF09-768834316C61} - C:\Program Files\HP\Digital Imaging\Smart Web Printing\hpswp_printenhancer.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: Spybot-S&D IE Protection - {53707962-6F74-2D53-2644-206D7942484F} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O2 - BHO: SSVHelper Class - {761497BB-D6F0-462C-B6EB-D4DAF1D92D43} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O2 - BHO: HP Smart BHO Class - {FFFFFFFF-CF4E-4F2B-BDC2-0E72E116A856} - C:\Program Files\HP\Digital Imaging\Smart Web Printing\hpswp_BHO.dll
O4 - HKLM\..\Run: [NeroFilterCheck] C:\Program Files\Common Files\Ahead\Lib\NeroCheck.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: [Logitech Utility] Logi_MwX.Exe
O4 - HKLM\..\Run: [HPDJ Taskbar Utility] C:\WINDOWS\system32\spool\drivers\w32x86\3\hpztsb0 7.exe
O4 - HKLM\..\Run: [Adobe Reader Speed Launcher] "E:\Program Files\Adobe\Reader 8.0\Reader\Reader_sl.exe"
O4 - HKLM\..\Run: [Kernel and Hardware Abstraction Layer] KHALMNPR.EXE
O4 - HKLM\..\Run: [HP Software Update] C:\Program Files\HP\HP Software Update\HPWuSchd2.exe
O4 - HKLM\..\Run: [QuickTime Task] "C:\Program Files\QuickTime\QTTask.exe" -atboottime
O4 - HKLM\..\Run: [iTunesHelper] "E:\Program Files\iTunes\iTunesHelper.exe"
O4 - HKLM\..\Run: [NvMediaCenter] RUNDLL32.EXE C:\WINDOWS\system32\NvMcTray.dll,NvTaskbarInit
O4 - HKLM\..\Run: [NvCplDaemon] RUNDLL32.EXE C:\WINDOWS\system32\NvCpl.dll,NvStartup
O4 - HKLM\..\Run: [nwiz] C:\Program Files\NVIDIA Corporation\nView\nwiz.exe /installquiet
O4 - HKCU\..\Run: [DAEMON Tools] "E:\Program Files\DAEMON Tools\daemon.exe" -lang 1033
O4 - HKCU\..\Run: [SpybotSD TeaTimer] C:\Program Files\Spybot - Search & Destroy\TeaTimer.exe
O4 - HKCU\..\Run: [EA Core] "C:\Program Files\Electronic Arts\EADM\Core.exe" -silent
O4 - HKCU\..\Run: [ctfmon.exe] C:\WINDOWS\system32\ctfmon.exe
O4 - Startup: Folding@Home 5.03.lnk = ?
O4 - Global Startup: HP Digital Imaging Monitor.lnk = C:\Program Files\HP\Digital Imaging\bin\hpqtra08.exe
O4 - Global Startup: Logitech SetPoint.lnk = C:\Program Files\Logitech\SetPoint\SetPoint.exe
O4 - Global Startup: Microsoft Office.lnk = C:\Program Files\Microsoft Office\Office10\OSA.EXE
O8 - Extra context menu item: E&xport to Microsoft Excel - res://C:\PROGRA~1\MICROS~2\Office10\EXCEL.EXE/3000
O9 - Extra button: (no name) - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O9 - Extra 'Tools' menuitem: Sun Java Console - {08B0E5C0-4FCB-11CF-AAA5-00401C608501} - C:\Program Files\Java\jre1.6.0_03\bin\ssv.dll
O9 - Extra button: Show or hide HP Smart Web Printing - {DDE87865-83C5-48c4-8357-2F5B1AA84522} - C:\Program Files\HP\Digital Imaging\Smart Web Printing\hpswp_BHO.dll
O9 - Extra button: (no name) - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.dll
O9 - Extra 'Tools' menuitem: Spybot - Search & Destroy Configuration - {DFB852A3-47F8-48C4-A200-58CAB36FD2A2} - C:\PROGRA~1\SPYBOT~1\SDHelper.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
O16 - DPF: {6414512B-B978-451D-A0D8-FCFDF33E833C} (WUWebControl Class) - http://www.update.microsoft.com/wind...?1186202894577
O16 - DPF: {6E32070A-766D-4EE6-879C-DC1FA91D2FC3} (MUWebControl Class) - http://www.update.microsoft.com/micr...?1186208054406
O16 - DPF: {8167C273-DF59-4416-B647-C8BB2C7EE83E} (WebSDev Control) - http://liveupdate.msi.com.tw/autobio...AB/install.cab
O22 - SharedTaskScheduler: Browseui preloader - {438755C2-A8BA-11D1-B96B-00A0C90312E1} - C:\WINDOWS\System32\browseui.dll
O22 - SharedTaskScheduler: Component Categories cache daemon - {8C7461EF-2B13-11d2-BE35-3078302C2030} - C:\WINDOWS\System32\browseui.dll
O23 - Service: Apple Mobile Device - Apple Inc. - C:\Program Files\Common Files\Apple\Mobile Device Support\AppleMobileDeviceService.exe
O23 - Service: Bonjour Service - Apple Inc. - C:\Program Files\Bonjour\mDNSResponder.exe
O23 - Service: InstallDriver Table Manager (IDriverT) - Macrovision Corporation - C:\Program Files\Common Files\InstallShield\Driver\11\Intel 32\IDriverT.exe
O23 - Service: iPod Service - Apple Inc. - C:\Program Files\iPod\bin\iPodService.exe
O23 - Service: Logitech Bluetooth Service (LBTServ) - Logitech, Inc. - C:\Program Files\Common Files\Logishrd\Bluetooth\LBTServ.exe
O23 - Service: NVIDIA Display Driver Service (nvsvc) - NVIDIA Corporation - C:\WINDOWS\system32\nvsvc32.exe