If you had got your Latitude E5400 unit without any Pipd DISPLAY1366X768 driver CD or the latter is lost, you may choose to follow the links below. Without a special Latitude E5400 driver to your unit, you won’t be able to use all its NEC functionality. The basic Pipd DISPLAY1366X768 driver from Windows is only able to support the minimum RJ45-RS232 set thereof. You are really in need of a fully-featured authentic Pipd DISPLAY1366X768 driver.
For Latitude E5400 download, please just follow the ThinkPad T510 link.