How did the HDRish make the BGs look crappy? I haven't noticed anything. But then again... I'm not really using HDRish as it was released. I had it edited down to 50% effectiveness.
I actually used a variant of the effect called HDRish Lite, which is also floating around the internet. The normal HDRish was almost always too strong. The Lite version still used to mess up the backgrounds though. If the mission had fairly detailed nebulas or planets in the background, they all looked blurry and lost a lot of fine details. The effect looked a lot better in some other games though. I used to have it on in Descent 2, Unreal and Deus Ex.
Among the currently available cards, you'll generally get better overclocks on Nvidia ones even though ATI cards are in theory more flexible due to their voltage options. The 7900GTs were monster overclockers for a long time and the 8800s are also going up pretty nicely. Of course, that doesn't mean much unless you take the stock performance into account too.
I can get 710mhz out of my X1900XTX at 1.425V, which is about a 9% increase. Anything higher than that needs further voltage increases, which pushes the temperatures too far up. The memory sucks and only goes up to 800mhz (from 775mhz) even with the VDDCI cranked way up, although it's just as well since these cards don't benefit much from any additional memory speed anyway.
