Update on 4GB Patch. This is indeed the trick to stabilising Oblivion, the base game will crash whenever more than 1.8GB is used (easy to do with mods). If you have the disk version you are lucky, the patch works fine.
If you have the Steam version the patch will not work. There is a workaround if you own a copy from Steam, but it's borderline against the rules here so I will only say look at OBSE/src/obse/loader_common/EXEChecksum.cpp line 224.
I've just had a chance to test this by running Oblivion in windowed mode with Task Manager running. It has fixed both my framerate issues and crash to desktops and it's fairly easy to see why.
A fresh game loading into the Imperial Docks area with QTP3/RAEVWD/Better Cities/Full Sliders and a bunch of other stuff uses around 1.7GB (without people replacers etc loaded), as soon as I zoned into the tunnel RAM usage hit 2GB. This would have been an instant crash to desktop on an unpatched Oblivion. Fast Travelling to the Dock area of Anvil took memory up to 2.4GB.
I took out Streamline as the guy who made OSR recommends against it, left the framerate capped at 30fps (enough for me and gives the game engine time to breathe for handling housekeeping/ai etc), did a full install of Better Cities with all districts and open cities. I also used OSR's heap replacement, using mode 6.
Framerates seemed to hover between 20-30fps in the Docks, though improved once everything loaded up. 30fps constant everywhere else. I suspect a faster CPU would have better framerates here, my i7 920 is only moderately overclocked to keep power/noise/heat down.
(WITH FULL SLIDERS)
Last edited: