So now ive bought a active adapter dvi -> active display port i plugged it into my pc and then turned it the computer my other 2 screens turned on but the 3rd just said sleep mode enabled and the screen turns black but it stays on. When i drag my mouse or a window to the right which is where the 3rd screen is they dissapear so technically the screen is connected but the screen just stays black any help guys thanks!
Install the latest catalyst suite from AMD. Then go into the catalyst control center and check that it can see all three displays. There should be an 'identify screens' option. Configure them as an eyefinity group.
If you want to test your adapter to see if it is working, then shut down the system, disconnect the other two monitors and boot with only the single monitor attached via the DP -> DVI adapter. It should work fine.
Also, what resolution are your monitors specifically?