HDR broken at 6xAA on X1950XTX Crossfire in Oblivion?

Update: 16 Jan 07 – downloaded latest Catalyst Drivers and this problem has been resolved – also noticed performance gains in this and other games

I know that earlier versions of the ATI Catalyst drivers did not allow anti-aliasing and HDR at the same time in Oblivion on the X1950XTX cards. Actually it is only by forcing the settings in Catalyst that it is now possible at all.

However, I have come across a slight glitch when you move from 4xAA to 6xAA and then on to 8xAA.

See the following shots and pay attention to 2 things:

1. The lighting bloom around the edge of the sword at 6xAA just does not exist.
2. There is an overal fogginess to the entire scene at 6xAA.

First, here is the 4xAA shot:

Oblivion X1950XTX Crossfire 4xAA Hosted on Zooomr

Next the 6xAA:

Oblivion X1950XTX Crossfire 6xAA Hosted on Zooomr

Finally the 8xAA:

Oblivion X1950XTX Crossfire 8xAA Hosted on Zooomr

I should point out that the 4x and 6x shots were with temporal anti-aliasing turn on although it actually makes no difference to the effect. Also, AF was at 8x with HQ turned ON and all other settings were at ON/Max – with max settings in Oblivion too.

The interesting thing is that between 6x and 8x is the point at which the second card kicks in and starts doing its thing with boosting AA.

With everything else almost maxed out 8xAA slows things down just a fraction too much, so I’m sticking with 4x as I can’t really tell the difference during the game anyway.