tgzuk 0 Newbie Poster

Hi guys , i have just replaced the power connector on a hp pavilion zt1000 notebook, and i am sure i have reconnected all cables etc but now when i try to boot up the damn thing it whirs like its try boot but then powers down after 4 or 5 seconds and the lcd shows off, any suggestions please as i have even had the board out the casing and tried it in case there was a short but still no joy !!