Okay, so I've played around a lot with settings in UT and in NVIDIA control panel, and have not yet found anything that does any good to the cause. Strangely it runs quite fine at around 95 fps, so for the moment I will stick to that number. Offline I would get smooth gameplay as high as 140 fps (did not go higher as I didn't see any reason why I should).
In my 9 years of UT I haven't played with vsync on, but I have always limited my fps to equally to the hz of my monitor, as going above have produced tearing more rapidly (might have just been in my head). I have never really been comfortable setting my fps higher than the monitor's hz, but I find myself just as uncomfortable having fps way lower than my hz!
I've also made sure that UT runs strictly on one core, first thing I learned when I obtained my first dual core cpu! Though I don't think modern hardware have anything to do with the stutter issue I am experiencing. I used to have the same problem when I tried to go above 100fps with my older systems back in 2003-2005, but I always thought it was a matter of monitor hz which is why I was surprised that UT would not run smoothly on 120fps with 120hz.
This is the latest edit of my attempt-for-120-fps ini. Only thing I have changed to make it run smoothly now is having frameratelimit set to 95. Eventually I found myself just flipping every option on/off to see if anything worked, but to no success.
Code:
[WinDrv.WindowsClient]
WindowedViewportX=1016
WindowedViewportY=741
WindowedColorBits=16
FullscreenViewportX=1280
FullscreenViewportY=1024
FullscreenColorBits=16
Brightness=0.900000
MipFactor=1.000000
UseDirectDraw=False
UseJoystick=False
CaptureMouse=True
StartupFullscreen=True
CurvedSurfaces=True
LowDetailTextures=True
ScreenFlashes=False
NoLighting=False
SlowVideoBuffering=False
DeadZoneXYZ=True
DeadZoneRUV=False
InvertVertical=False
ScaleXYZ=1000.000000
ScaleRUV=2000.000000
MinDesiredFrameRate=120.000000
Decals=False
NoDynamicLights=False
SkinDetail=Low
UseDirectInput=False
ParticleDensity=0
NoFractalAnim=True
TextureDetail=Low
[OpenGLDrv.OpenGLRenderDevice]
Translucency=True
TruFormMinVertices=0
TruFormTessellation=3
UseTruForm=False
ZRangeHack=False
AAFilterHint=0
NumAASamples=0
UseAA=False
RequestHighResolutionZ=True
MaskedTextureHack=True
SmoothMaskedTextures=False
FrameRateLimit=120
SwapInterval=0
UseVertexProgram=False
UseCVA=False
UseMultiDrawArrays=False
TexDXT1ToDXT3=False
DynamicTexIdRecycleLevel=100
CacheStaticMaps=False
UseTexPool=True
UseTexIdPool=True
UseSSE=2
BufferTileQuads=False
BufferClippedActorTris=False
SinglePassDetail=False
SinglePassFog=False
ColorizeDetailTextures=False
DetailClipping=False
UseDetailAlpha=True
DetailMax=0
RefreshRate=120
MaxTMUnits=0
NoFiltering=False
NoMaskedS3TC=False
MaxAnisotropy=0
UseTNT=False
Use16BitTextures=False
UseS3TC=False
UseAlphaPalette=False
AutoGenerateMipmaps=False
UseTrilinear=False
UsePrecache=False
AlwaysMipmap=False
ShareLists=False
UsePalette=False
UseMultiTexture=True
UseBGRATextures=True
UseZTrick=False
MaxLogTextureSize=8
MinLogTextureSize=0
MaxLogVOverU=8
MaxLogUOverV=8
OneXBlending=True
GammaCorrectScreenshots=True
GammaOffsetBlue=0.200000
GammaOffsetGreen=0.000000
GammaOffsetRed=0.200000
GammaOffset=0.650000
LODBias=-15.000000
DetailTextures=False
DescFlags=0
Description=
HighDetailActors=True
Coronas=False
ShinySurfaces=False
VolumetricLighting=False
Use4444Textures=True