TR Legend Next Gen Issue

Here's a post I've placed elsewhere... This is an issue I'm about to give up with. Any suggestions would be greatly appreciated. This is something that, even if I were to try to put out of my mind, will never go away...

I'm running into a problem with Tomb Raider Legend that I'm hoping someone could help me out with...

I've recently put a new machine together, here are the specs:

Mobo - Asus P5ND2-SLI, BIOS revision 0304
CPU - Intel P4 3.06 GHz
RAM - 2 GB OCZ Gold PC 5400 667 MHz DDR2, 4-4-4-12 timing
PSU - OCZ GameXtreme 700W
GPU - MSI NX7950GX2 dual GPU @ 500 MHz each, 1 GB DDR3 (512 MB per GPU) - memory clock @ 1200MHz
video driver - ForceWare v91.31
TRL Game v1.2 (latest updates applied)

When I play Tomb Raider Legend with next generation content turned on, as Lara approaches areas in the game that haven't been explored (backdrops not yet rendered), the game becomes terribly choppy, to the point of outright freezing up on me until it does whatever it's doing, then resumes. If I turn Lara around and move her to a backdrop area that has already been previously rendered by the card, it runs perfectly smooth, without a single drop in frame rate.

I don't get it... I have Oblivion maxed out as far as I can take it with native 1280x1024 resolution, and the game functions great. This is one awesome video card. But I can't seem to find a solution for this problem with Legend. I have tried tweaking all sorts of things in the video card settings, different combos of settings, etc., set up custom settings for "trl.exe" in the nVidia control panel, you name it... I don't know, maybe I'm not tweaking settings properly.

Does anyone have any idea what the optimal settings for this game should be with a 7950 GX2? I've attempted to seek support from Eidos, but their idea of support is to select your game from a drop-down menu and direct you to tech support "FAQ"; not much help, if you know what I mean...

This machine I've built surpasses the requirements for the next generation content, but I still can't seem to get this game to function properly. This is one of the games that motivated me to build a new system, so you can understand my frustration with this.

Any suggestions would be greatly appreciated. Thanks in advance!