No activity on the lots

[Lisen 0]

Hi, I have a problem with the activity that occasionally disappear from all the lots, no people, no cars, etc. On the streets there are lots of people and cars. The only site of activity is Ford-site where there is both public and cars.Sometimes it works but often not. Sometimes I restart the program and then it works as it should. It is very annoying because I really like all the fun details in the game.

What's going on and what can I do to make it always work?

Can I force the application to always show everything?

I have test with different graphic settings but usually I play with medium video quality, window mode and anti-aliasing disabled.

The city size does not matter, it is the same for small cities and very big, 7 million inhabitants.

My computer is an Intel Core Duo E6600, 2.4 GHz

4096 MB DDR2 SDRAM

nVIDA GeForce 8800 GTS 640 MB GDDR3 SDRAM

Will it work better with another graphic card?