I HAVE FOUND A WORK AROUND, WORK 100% with guarante
If testing (press and keep "Fn" and press the power button) of your Inspirion 1525 is ok, do the following
1) press and keep the button "F2", press and release the power button
2) after about 10s, you will see light on the display, release F2
voila (try again if it not work the first time, turn all off before you try)
why F2? because it is for the BIOS setup, I want to check the bios settings, and then I saw this trick by using F2 to "trigger" the display. There must be a bug in Dell POST check since it "thinks" there is something wrong and then it halts the whole check.
GL
Tuan