Get yourself some magnifying glasses and put them on, search the board for a short or broken trace. UE8 is a "Usual Suspect" on Video Logic Board Problems. But also, there is a lot of Flux on the board from your soldering. Get a bottle of Acetone and strong Isopropyl Alcohol, and wipe that board down with paper towels and q-tips soaked in Acetone, and then rinse it off with the alcohol and let dry. That will clear up the flux off the board and let you inspect the work done on it.