Hello, its been a long time since I have asked for help

but ran into a recent problem. The expansion for a game I play recently came out this week and now all of the sudden I am getting a "runtime error"and I get booted to the desk top. I don't remember the exact wording of the error but it was something about "runtime error application requested XXXXXX amt of memory but avaliable memory is only XXXXX, then I get a 2nd box that pops up and tells me the filer name of the application which is the game file for the game I am playing, then once I click ok on the error it drops me to desk top. I then can log right back into the game but then it happens again a few min later.
I read on the EQ2 forums that others are having this same problem and some said it was only happening with the new part of the game. Some said they had to lower thier graphics settings or change thier card to a X1 or X2 for AGP. I tried to lower my settings on the game which I normally run at max settings ( and have always run at max settings whith no problems at all with game until this expansion came out). I tried to lower my settings but still got same error.
I know I have more than enough memory (system memory and VC memory)
Currently I am running:
CPU--Intel Core 2 Duo E6750 2X 2.66GHz/wMB L2 cache
Asus P5N-E SLI 650i
3GIG Corsair XMS2 (three 1 gig chips)
WD Raptor WD1500AFD 150GB HD
Nvidia GeForce 8800 GTX 768MB
OS Windows XP Home
1000WaTT PS
So as you can see I have more than enough PC to run this game and then some, and I have been running this game fun until thsi expansion came out.
Any ideas what I should do or what I can try??