I AM using fully opengl compliant extensions. Either way, it queries the ATI card first to check it will support them, and it says it will
As Rovastar points out, i think the framerate halving in R4 is simply the ATI card struggling. It happens on NV cards too - after all its doing twice as much work.
As for vsync - R4's vsync tries to keep to the given framerate. If rendering takes more time, it waits less, so the framerate halving isn't due to that, and increasing the limit won't help it. I think what you're finding is that the FPS meter 'smooths' out FPS values over time, so if you start with a large framerate it won't appear to go down as far in the first second as if you started off with a lower value. I was told by someone that vsync had gone. They must have got confused or something. grr.
Its possible ATI's OpenGL uses ATI's DirectX driver. I'm not sure about that though. It might be possible that the new ATI cards are incapable of rendering to the old format - it wouldn't really surprise me. Keep trying tho' - if you can lip them back it'd be way faster.
PBuffer reusing seems to work fine - there are a few reasons why it might appear wrong... Main one is that PBuffers can be different sizes - not just the 'default'. A few of scenes now use smaller pbuffers either for speed or other reasons (128x128 or 256x256 mostly) - these can't be reused as larger pbuffers for obvious reasons so on scenes that don't use them they're unused. Also, some pbuffers are used during rendering and then freed before the end of the frame - you don't see these.
The halt on pbuffer allocation is, again, not my fault. Nor is the random crap on the screen - it may be R4 that is causing it, but its def. and ATI bug since OpenGL should NEVER be able to do that.
as for fonts, i can't use the TTF ones (i use some standard ones for 3D text, but not bitmaps). The fonts have a tinted black edge on them so you can see them on white backgrounds, and you don't get that from TTF. It could be worked out on load, but it'd take ages and there is absolutely no point.
The cube is gay. I'm damned if i can figure out whats wrong, but its not major, and it wasn't on my list of vital things to do so it hasn't been looked at much
I load quite a few textures, but most of them are smallish. 256x256 or something. You can count the entries in the log file if you want to :p The major hit will be pbuffers, since they have to contain all the extra rendering info. I could modify R4 a load again and copy back to normal textures, but to be honest it'd be pretty slow too.
I probably missed out something there so let me know if i did...