Is it to late for you to return this expensive card ?
Don't you think something is wrong if you can't easily get up and running a single monitor configuration ? I usually don't like people trying to answer troubleshooting problems with more questions. But I will be honest with you, the whole display port situation is a giant grey area it seems. What works with what card and will work with what monitor is hard to pin down.
There was no dongles in the box to help you get going ?