I know many of the guys have this problem but mine is unique.
I bought a Zotac GT240.for my dell inspiron 518.which has a 300w psu.which i guess can handle the gt 240 well.but the problem is when i connect the graphic card to monitor it crashes just before the windows screen.so i went to my friends home and connected it there and it worked flawlessly .so i thought the psu was the problem but on connecting the same psu to my system resulted in the same problem.
the monitor displays the bios.
moreover the problem occurs only if i connect the monitor to my gpu.i tried removing the old intel display drivers also. i also tried installing windows with the gpu but on windows xp it just causes restart after loading files and in windows 7 it causes the setup to hang.
i also tried boot the minxp in hirens boot cd and minixp boots up without problems.