Wow, you cut some of those pins off really short. Check with a flash light to see if any of the pins got out of place in the hu card slot. If the pins are super short on the hu card end there is a risk of them heating up too much when soldering(if iron is held on too long)and moving/melting out of place. Also, check the traces on the underside of the board.
Does the white screen happen even without a card inserted? Meaning no CD bios screen? These traces are typically damaged from the bottom side of the board. So make sure all the pins traces have good connection on the bottom side.