I reinstalled A7 again but nothing changed , and i did a virus test but i didnt catch any one, I realized something which is when i set the rendering library to gxl2base32.dll , the pc stands for longer time without any crashing , but it crashes in the end
so it looks like a direct X problem

another thing : my pc is not old at all
pentium(R) 4 cpu 2.40 GHZ
2.39 GHZ 480 MB ram

sorry for that question , I found a wed.txt file in the GS directory,
does it supposed to be empty?? cuz it is
thats all i can tell

thanks for your help

ps: i installed a7 trial on another pc(not old one)like mine, and it gave the same problem