
Try disabling and re-enabling your card.If you have an AMD Radeon card, try the following: If your card is not affected by this, make sure it is an AMD Radeon card. If all of this fails, either your card requires some other feature to be disabled, one of your monitors no longer works, or your card is incompatible with these steps. You do not have to uninstall the drivers, and you only need to do this if Crimson Manager complains or malfunctions. (Conditional) If you have Crimson Manager, you may have to reinstall it.This makes ABSOLUTELY sure no remnants stick in RAM and that all capacitors are discharged. CAREFULLY remove the CrossFire cable from BOTH cards.

This will make sure no power is left in the system this is always a good thing to do when changing hardware. If you do not have Catalyst Control Center (or have the Crimson Manager) do the following: If you have Catalyst Control Center, go to Performance -> AMD CrossFireX and select "Disable AMD CrossFireX".

Step 1: Simple Fixes / Check Your Configuration

It would be appreciated if you would report if this worked for you, and the card series you got working. This tutorial is only tested on Radeon HD 5xxx series. This is actually REALLY simple to fix but will impact your cards' performance.

Since I recently had this problem and fixed it, I might as well share the solution.
