The location and/or reputation of your medical school plays an insignificant role IMHO for the selection of *most* residencies. To be sure, for some highly competitive residencies at top tier programs, your undergrad rep may help the PD choose between you and all the other applicants with great USMLEs, LORs, grades, personal statements, etc.
However, IMHO for most residencies MUCH MUCH more important will be your scores, LORs, grades, and reason for wanting to choose a certain residency (ie, being from the Northeast or a program having a specific experience which you desire during your residency).
You've accomplished the most difficult step in getting a residency...getting into a US medical school.