I can have the game maxed out easily and all that and it runs fine that is till I run near a NPC then all hell breaks loose. It seems fine around non-combatant NPC's but once in combat it gets even worse then it already is. I saw in another thread that I should lower my res and I did so and it helped just a tad but it is still that and noticable. Any ideas?
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System Information
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Time of this report: 1/9/2011, 21:07:25
Machine name: USER-C0E8DB9670
Operating System: Windows XP Professional (5.1, Build 2600) Service Pack 3 (2600.xpsp_sp3_gdr.100427-1636)
Language: English (Regional Setting: English)
System Manufacturer: System manufacturer
System Model: System Product Name
BIOS: BIOS Date: 08/27/10 17:22:44 Ver: 08.00.15
Processor: Intel® Core™ i5 CPU 760 @ 2.80GHz (4 CPUs)
Memory: 3582MB RAM
Page File: 921MB used, 4542MB available
Windows Dir: C:\WINDOWS
DirectX Version: DirectX 9.0c (4.09.0000.0904)
DX Setup Parameters: Not found
DxDiag Version: 5.03.2600.5512 32bit Unicode

---------------
Display Devices
---------------
Card name: NVIDIA GeForce GTX 460
Manufacturer: NVIDIA
Chip type: GeForce GTX 460
DAC type: Integrated RAMDAC
Device Key: Enum\PCI\VEN_10DE&DEV_0E22&SUBSYS_13733842&REV_A1
Display Memory: 1024.0 MB
Current Mode: 1920 x 1080 (32 bit) (60Hz)
Monitor: Plug and Play Monitor
Monitor Max Res: 1600,1200
Driver Name: nv4_disp.dll
Driver Version: 6.14.0012.6099 (English)
DDI Version: 9 (or higher)
Driver Attributes: Final Retail
Driver Date/Size: 10/16/2010 13:55:00, 6359552 bytes
WHQL Logo'd: Yes
WHQL Date Stamp: n/a
VDD: n/a
Mini VDD: nv4_mini.sys
Mini VDD Date: 10/16/2010 13:55:00, 9623680 bytes
Device Identifier: {D7B71E3E-4D62-11CF-214C-7F3300C2CB35}
Vendor ID: 0x10DE
Device ID: 0x0E22
SubSys ID: 0x13733842
Revision ID: 0x00A1
Revision ID: 0x00A1
Video Accel: ModeMPEG2_C ModeMPEG2_D
Deinterlace Caps: {6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(YUY2,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(YUY2,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(UYVY,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(UYVY,YUY2) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(YV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(YV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
{6CB69578-7617-4637-91E5-1C02DB810285}: Format(In/Out)=(NV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_PixelAdaptive
{335AA36E-7884-43A4-9C91-7F87FAF3E37E}: Format(In/Out)=(NV12,0x3231564e) Frames(Prev/Fwd/Back)=(0,0,0) Caps=VideoProcess_YUV2RGB VideoProcess_StretchX VideoProcess_StretchY DeinterlaceTech_BOBVerticalStretch
Registry: OK
DDraw Status: Enabled
D3D Status: Enabled
AGP Status: Enabled
DDraw Test Result: Not run
D3D7 Test Result: Not run
D3D8 Test Result: Not run
D3D9 Test Result: Not run

-------------
Sound Devices
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Description: NVIDIA High Definition Audio
Default Sound Playback: Yes
Default Voice Playback: Yes
Hardware ID: HDAUDIO\FUNC_01&VEN_10DE&DEV_0012&SUBSYS_10DE0101&REV_1001
Manufacturer ID: 1
Product ID: 100
Type: WDM
Driver Name: nvhda32.sys
Driver Version: 1.01.0009.0000 (English)
Driver Attributes: Final Retail
WHQL Logo'd: Yes
Date and Size: 9/7/2010 15:08:58, 100712 bytes
Other Files:
Driver Provider: NVIDIA Corporation
HW Accel Level: Full
Cap Flags: 0xB5B
Min/Max Sample Rate: 44100, 192000
Static/Strm HW Mix Bufs: 1, 0
Static/Strm HW 3D Bufs: 0, 0
HW Memory: 0
Voice Management: No
EAX™ 2.0 Listen/Src: No, No
I3DL2™ Listen/Src: No, No
Sensaura™ ZoomFX™: No
Registry: OK
Sound Test Result: Not run

Description: HD Audio rear output
Default Sound Playback: No
Default Voice Playback: No
Hardware ID: HDAUDIO\FUNC_01&VEN_1106&DEV_0397&SUBSYS_104383C4&REV_1000
Manufacturer ID: 1
Product ID: 100
Type: WDM
Driver Name: viahduaa.sys
Driver Version: 6.00.0001.7500 (English)
Driver Attributes: Final Retail
WHQL Logo'd: Yes
Date and Size: 9/17/2009 06:00:30, 1399680 bytes
Other Files:
Driver Provider: VIA Technologies, Inc.
HW Accel Level: Full
Cap Flags: 0xF5F
Min/Max Sample Rate: 8000, 192000
Static/Strm HW Mix Bufs: 1, 0
Static/Strm HW 3D Bufs: 0, 0
HW Memory: 0
Voice Management: No
EAX™ 2.0 Listen/Src: No, No
I3DL2™ Listen/Src: No, No
Sensaura™ ZoomFX™: No
Registry: OK
Sound Test Result: Not run

It's mostly due to the AI being a huge memory hog in this game. Being around a lot of NPCs processing their AI packages all at once is guaranteed to send your FPS plummeting.

Not much that can be done about it, unfortunately. The Radiant AI coding is just another of the badly optimized portions of this game. Granted, Bethesda was building this game for next-gen hardware at the time, so this is mostly because they didn't really know how they would need to optimize this game.

Just one of the things we need to live with.

What does your framerate drop to in combat?

Lowering your resolution probably did not help the real issue, since your graphics card couldn't possibly be struggling with Oblivion (unless you added a bunch of mods to it.) Are you playing vanilla Oblivion? The NPCs' AI packages are hurting your CPU, and lowering the res mainly just relieved your graphics card a little bit. I'm kind of surprised you saw a boost from that, honestly (unless, again, you are played a game modified with many texture replacers.) Do you have Anti-virus and other applications running in the background? Did you try running the game after a clean boot?


Edit: If you have AA turned on, turn it off. That would certainly give your system a boost...