Hello Hunter,
Take a look at the following link to find out how to perform a self-calibration of your E Series board:
http://zone.ni.com/devzone%5Cconceptd.nsf/webmain/294141819729D396862568690070E2A9
I believe that you can also self-calibrate your board by running the E Series Diagnostic Utility found here:
http://www.ni.com/support/selftest/
Take care,
E.Lee
Eric
DE For Life!