190.16 on 9800GTS hangs whole system

Hi, please, help me figure out such problem, I need properly working NVIDIA driver with CUDA support. My system is laptop Gateway 7807 with 9800 GTS on board, yesterday I have tried to install 190.16 ver, after sucessful completing of installing process I was unable to load Ubuntu 9.04 amd64, screen was black and any output, CTRL_ALT_DEL also didn’t work. Actually I get this driver from NVIDIA CUDA section driver download http://www.nvidia.com/object/cuda_get.html, and there one thing that confuse me- why every day they change beta drives version? First day 190.16 then 190.18 then again 190.16.

On my laptop with 8600 GT & Ubuntu 9.04 this driver works:
This is not special CUDA-driver but regular NVIDIA-driver with CUDA support (I don’t know is there any difference between them now).
CUDA Toolit 2.3 & SDK 2.3 also work with it.

At last it works, yes, I have installed 190.18 too, and CUDA works as well. So I don’t know what was the problem with 190.16