Here is a handy tool that helps you detect short circuits in your DisplayPort and Mini DisplayPort cables like a pro. The T040-001-DP has adjustable test modes (continuity and sweep) that you can switch at the flip of a switch. It displays 19 pin to pin wire map and shield connection status.
Tripp Lite’s T040-001-DP cable tester is compatible with DisplayPort 1.0 to 1.4 cables up to 49 feet. It ships with the main tester, remote identifier, and a carrying case.