2008 macbook pro issue

i shut off my mac yesterday and when i went to turn it back on it powered up ,made the booting noise , but the screen doesn't turn on or keyboard doesn't light up .

has anyone came across this issue before

Try closing the lid and reopening it again. There's an issue with the video cards in those.. if this is the issue you're encountering Apple will replace the logic board.

i tried that a few times still didnt work, thanks for the advice

MacBook Pro: Distorted video or no video issues <-- read this then

Now, you may end up with no SN in system profiler.. I did.. not a huge deal though, someone just forgot to set it in the EPROM when they replaced it.

I second this^^. This is just about the only time I will tell people just to take it to apple and have them deal with it. It is a 1000 dollar repair for which nvidia will be footing the bill (but dont worry you will just walk out without paying a dime).