Dell latitude E5410 i3 core2quad boot issue

Hi guys, this is my first post so here goes.
i bought this laptop 2011 model it has booting issues. i can get into bios & select boot device but that's it.
things i have done.
removed heatsink cleaned & applied new thermal paste to cpu.
cleaned fan.
changed harddrive
changed ram
it will not boot to win 7 as it was when i bought it.
so anyone got ideas as what might be the problem.
would appreciate anything as i'm all out of answers. thanks

 

Did you reinstall the OS (Win7)? If you changed the HDD, you need a reinstall of course.

Any other symptoms?

 

Thanks for the reply.
yes i reinstalled windows 7 of course it won't run without it.
it boots to post ok then it stalls.

 

Did u run F12 -> Diagonostic?

Is bios up to date?