i finally add more memory another 256 now i have 516 and still have the same problem.
sadly you will have hard time due to your sis chipset (not or badly supported by recent kernels), and too low ram quantity.
that said, you might download Jaunty i386, which i suppose will be able to use your hardware as it is, or try some other OS proposed in a previous post.
http://old-releases.ubuntu.com/releases/9.04/
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