UPDATE: The power cord extension got a bit fried--not totally, it still works when connected to other parts so I just wrapped it with an electric tape. The red coating melted partially but the wire inside seems fine.
The PC still won't boot when the hd is connected to the power cord (the cord immediately connecting to the PSU). When it's an extension, the cord gets fried. >__<
IDE cable seems fine though, when connected to the other HDD. I tested both pins.
thanks for the replies :)
i still need other answers as to why this is happening tho.