I've been playing Skyrim on PS3 but I finally decided to try it out on my computer. I knew it wasn't going to work that well (I'm on an iMac, porting Skyrim, with a video card with only 256 vRam).

Initially the game was unplayable with an FPS of about 2-3. After a few adjustments (low settings, shadows off, FXAA off) it's playable but still really laggy in some areas.

What else can I do to make it perform well? I tried messing with some other values in the SkyrimPrefs.ini file but then just made it worse, since I don't really know what most of them mean or do. Are there any values I can change that may improve framerate, or any mods I can download?

Also, is there a way to see what my antialiasing is set to (maybe in a preferences file)? For some reason in the Mac port there isn't an option in the preferences window to turn antialiasing on or off...(or if anyone is familiar with the port, how do I see that preference?)

Here are my current SkyrimPrefs.ini settings (in My Documents):

[Display]
iTexMipMapSkip=1
bFXAAEnabled=0
fMeshLODLevel2FadeDist=3072.0000
fMeshLODLevel1FadeDist=4096.0000
fSpecularLODStartFade=200.0000
fLightLODStartFade=200.0000
fTreesMidLODSwitchDist=0.0000
iShadowMapResolution=512
fShadowBiasScale=0.5000
iShadowMaskQuarter=3
iBlurDeferredShadowMask=0
fShadowDistance=0.0000
iMaxDecalsPerFrame=0
iMaxSkinDecalsPerFrame=0
iAdapter=0
iSize W=1920
iSize H=1200
iMultiSample=0
iMaxAnisotropy=0
iPresentInterval=0
bFull Screen=1
fInteriorShadowDistance=0.0000
bFloatPointRenderTarget=0
fGamma=1.0000
iShadowFilter=3
fDecalLOD2=1500.0000
fDecalLOD1=1000.0000
fShadowLODStartFade=200.0000
iTexMipMapMinimum=0
bTransparencyMultisampling=0
iWaterMultiSamples=0
iShadowMode=3
bTreesReceiveShadows=0
bDrawLandShadows=0
bDrawShadows=1
fLeafAnimDampenDistEnd=4600.0000
fLeafAnimDampenDistStart=3600.0000
fMeshLODFadePercentDefault=1.2000
fMeshLODFadeBoundDefault=256.0000
fMeshLODLevel2FadeTreeDistance=2048.0000
fMeshLODLevel1FadeTreeDistance=2844.0000
iScreenShotIndex=0
bShadowMaskZPrepass=0
bMainZPrepass=0

[Imagespace]
iRadialBlurLevel=0
bDoDepthOfField=1

[LOD]
fLODFadeOutMultActors=2.0000
fLODFadeOutMultItems=1.0000
fLODFadeOutMultObjects=2.5000
fLODFadeOutMultSkyCell=1.0000

[Grass]
fGrassStartFadeDistance=0.0000
b30GrassVS=0
fGrassMaxStartFadeDistance=7000.0000
fGrassMinStartFadeDistance=400.0000

[Decals]
bDecals=0
bSkinnedDecals=0
uMaxDecals=0
uMaxSkinDecals=0
uMaxSkinDecalsPerActor=0

[TerrainManager]
fTreeLoadDistance=12500.0000
fBlockMaximumDistance=75000.0000
fBlockLevel1Distance=25000.0000
fBlockLevel0Distance=15000.0000
fSplitDistanceMult=0.4000
bShowLODInEditor=0

[BlurShaderHDR]
bDoHighDynamicRange=0

[BlurShader]
bUseBlurShader=0

[Launcher]
bShowAllResolutions=1
uLastAspectRatio=4

[Water]
iWaterReflectHeight=512
iWaterReflectWidth=512
bUseWaterDisplacements=1
bUseWaterRefractions=1
bUseWaterReflections=1
bUseWaterDepth=1

[MAIN]
fSkyCellRefFadeDistance=150000.0000
bGamepadEnable=0
bCrosshairEnabled=1
fHUDOpacity=1.0000
bSaveOnPause=0
bSaveOnTravel=0
bSaveOnWait=0
bSaveOnRest=0

[GamePlay]
bShowFloatingQuestMarkers=1
bShowQuestMarkers=1
iDifficulty=2

[Interface]
bDialogueSubtitles=0
bGeneralSubtitles=0
bShowCompass=1

[Controls]
fMouseHeadingSensitivity=0.0420
fGamepadHeadingSensitivity=1.9000
bAlwaysRunByDefault=1
bInvertYValues=0
bGamePadRumble=0

[Particles]
iMaxDesired=750

[SaveGame]
fAutosaveEveryXMins=60.0000

[AudioMenu]
fAudioMasterVolume=1.0000
fVal7=1.0000
uID7=0
fVal6=1.0000
uID6=0
fVal5=1.0000
uID5=0
fVal4=1.0000
uID4=0
fVal3=1.0000
uID3=466532
fVal2=0.8000
uID2=554685
fVal1=0.8000
uID1=1007612
fVal0=1.0000
uID0=94881

[Clouds]
fCloudLevel2Distance=262144.0000
fCloudLevel1Distance=32768.0000
fCloudLevel0Distance=16384.0000
fCloudNearFadeDistance=9000.0000

[General]
iStoryManagerLoggingEvent=-1
bEnableStoryManagerLogging=0

[Trees]
bRenderSkinnedTrees=1
uiMaxSkinnedTreesToRender=40

Thanks in advance.

sorry mate but i think you have done most of the things you can really do with your rig , the only thing i can think of is lowing the resalution lower then 1920x1200 say into 600x800 and then put it into windowed mode to just play it on a small window on your desktop ( not in full screen)
other then that im sorry your 256 vram is not going to cut it ..
good luck mate in your quest to play it with more fps

try lowering, maxskinnedtreestorender, under trees, 30-20 maybe, also terrainmanager, the terrain manager settings is related to distant object detail, try lower some of them, i think the maxtreestorender is how many trees on screen im not sure though

Okay, I've gotten it to perform pretty well outdoors (patching it helped but I could only manage to patch it to 1.3.1 since I can't figure out how to access steam through the mac port), but for some reason I get a lot of FPS drops in dungeons (particularly caves and forts). I'm not sure why; I've tried a lot of different stuff to no avail (I've used mods to turn off fog, I've turned down water graphics, etc.)... It's weird because it runs great in Whiterun or Solitude (where there is a going on) but in a little fort it lags like crazy. No problems at all in bigger dungeons like Blackreach, just in cramped spaces. Maybe it's lighting?