From a debug perspective, we might require additional information (as there are a broad host of problems that could be the issue).
The answer depends on what "no video" means.
Do you see the bios screen? Is there a windows logo before video is lost?
If yes...
Assuming you are running Windows, press F8 on boot and see if you can bring up safe mode.
That indicates a driver problem.
If no...
The problem is probably in hardware, but that does necessarily not mean the card is broken.
Does the MB post (Are there any beep patterns from the MB)?  If there is a pattern (not a single beep) you need to look up that pattern in your manual.
That could be a power supply connection issue or a host of other problems.