H and V synch don't visibly look shorted, but they don't particularly look great. Use a multimeter in continuity or resistance mode to check for a short between two lines. I would recommend checking resistance, as sometimes a resistance that is normal will still be below the threshold of what the DMM considers a short (not in the case of H/V sync, but still good practice). If you have 0 ohms between two lines, that's a dead short right there. Aside from that, all of those solder joints still look really cold, you really need to be using flux and a good, temperature controlled iron (I typically keep mine set to 650F/350C, 750F/400C for big planes). Having the ability to know that your solder joints are all solid is key in being able to track this issue down.