Thought I'd try Oblivion again after a minor upgrade to my aged PC.

I've noticed that many of the tweaks we used to use are gone from the INI file:

o bUseThreadedTempEffects=1 (default 0)
o bUseThreadedParticleSystem=1 (default 0)
o iNumHavokThreads=3 (default 1)
o bLoadBackgroundFaceGen=1 (default 0)
o bCloneModelsInBackground=1 (default 0)

? iPreloadSizeLimit=104857600 (default 26214400)

and so on.

I suppose the final version of the game changed all of this. Now I'm wondering if there are any effective tweaks left?

What tweaks should I then try on an older PC with 2Gb of RAM? Oh, I did find and install the "Unofficial Oblivion Patch."

Thanks.

Not really. Apart from a few minor adjustments (http://tescosi.com/wiki/Oblivion:Oblivion.ini), the default INI from 1.2.0416 is pretty much fine. All the multithreading and memory adjustment tweaks have been found to do absolutely nothing.