Touchpad Doesn't Work When computer is plugged in

Okay...so, a while back, my computer had a problem where the computer would say that it's "plugged in, not charging." I fixed this by getting a new adapter. (http://www.amazon.com/gp/product/B00763WKZW/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1)

While the charging problem is fixed, whenever I plug my computer in with this adapter, the mouse becomes erratic. I can do basic navigation, then the cursor flips out and flies over what I'm about to click, so aiming for anything is like running on ice.  I read a few things online as to what this is, and  wound up updating my mouse driver and BIOS, even "releasing flea power" (Either I did it wrong or it didn't work) This has done nothing for this problem. I don't want to have to replace this computer, so if you have any advice on how to fix this, it would be really appreciated. Thanks. 

BTW this is a Dell Inspiron N5110