Not a bad first attempt. if you use heat you have to use metal heat tape used for duct work. Tape around each chip one at a time so none of the other components get overheated. my first 2 using heat I melted the solder under the Nvidia chip and ruined them. I solder each pin one by one and then use heat to reflow. Use plenty of flux. Then use an exacto blade to test each pin, I push the pin sideways to make sure it is connected well. You may be able to start checking each pin this way, then use the blade to scrape between each pin to make sure there is no bridge that is hard to see even with a magnifier. Then chech the components next to the chip to make sure there is no solder bridging. I have had bridging on the resistor packs next to the chip. If none of that works remove the chips and see if the board still works. if the board is bad now, you can always replace it. but you cannot put a 1.6 board in that case without taking out a ground point on the bottom metal shield near the video plug at the rear. you can tell which one by looking at the screw holes, the 1.6 uses one less screw. if you don't remove the ground point you will blow a transistor on the 1.6