Re: TP Link WR1043ND 11n gigabit router
This is how I found chips to do these upgrades. First I read all the great posts on this forum about doing this kind of thing. Then I looked up the data sheet from the verified working memory chips, then found a double sided 512MB SODIMM on ebay that showed a good photo of the chips, then I looked up its data sheet and compared them to the verified ones. Double sided 512MB SODIMM work because they have 8 64MB chips, 8 x 64 = 512. Single sided 256MB chips should also work.
While waiting for them to arrive, I practiced on some PC133 desktop memory, desoldering and resoldering the chips and testing to make sure they still worked, then moved on to a DDR stick and did the same thing. DDR is harder because the pins are smaller and closer together and I ruined several DDR sticks before I got the hang of it. When I was sure I could do this every time, I upgraded a router and it worked.