A lot of these youtube fixes end up with people destroying their board. By the time you buy all the proper equipment, you could have gotten it fixed by someone else for way less.Heatgun. Lots of tutorials on YouTube
Make sure to protect everything. I use foil over everything but the gpu CPU ram etc
E73 can also be a partially dead GPU which needs to be replaced. If this console hasn't been worked on by others, a GPU reflow will most likely fix it. If it's the SB, sure a reflow will fix it (I've never had an E73 that was the SB, ever). If it's the network chip, it's usually E76, in which case it would have to be replaced, not reflown--these chips use J-leads so they never get cold solder joints like BGAs do.This can be caused by a bad network chip. If your house was struck by lighting you will get this err.
Southbridge reflow can fix this, but more than likely its your ethernet/network chip
does anyone know how to fix the E73 error (secondary error code 1021)
the x clamps have been replaced and new thermal paste applied.