Without hot air gun, I upgrade my TP-LINK TL-WR841N to 64MB RAM using x-knife
https://scontent.fhan2-2.fna.fbcdn.net/v/t1.0-9/14611004_1356737074351123_2400229294878534582_n.png?oh=d2bfd4b315e812bb0b166a00142dcd00&oe=5893BF86

https://www.youtube.com/watch?v=AlMYXP1OzWw