I just installed AM with my 1.79, no WA, no custom content game and after 5 minutes or so of normal gaming the game crashes to the desktop. Advice?

Thank you very much for the input, Pescado. Is there anything I can do to prevent this overheating or I am doomed to live with it?

I'm not sure what to do with this. I have a GeForce 8500, drives updated. Every time I'm playing, I know it's just a matter of time until the game starts showing some graphics weirdness (sims becoming invisible, black spots all over the screen) and then the game freezes. The error message is:
"Direct3D returned an error: D3DERR_NOTAVAILABLE! The application will now terminate".
Please, do any of you have any idea of what's going on? Any help would be much appreciated. Restarting the game every 20 minutes or so is driving me crazy.

Pescado, thank you very much. I already killed two sims and everything seems back to normal.

Edit: Oops, not so normal after all. Now my sims can't "Propose", the option disappeared. Is it related?

I'm not sure of what's going on here... I started a new hood (I have all the Eps and stuff pakages), with clean templates and everything. But everytime Death comes for a sim, she freezes the game. Death stands there, wearing her flower necklace, and everything stops working, I can't save or leave the game.
I tried forcing errors with the lot debugger, I checked for hack conflicts (none), but I have no idea of what's causing this. Could someone please help me?
Thank you,
cyberwitch