3 Displays with HD 5800

[Hunter_wow]

Hi. I´m trying to get Eyefinity to work for 3 displays with "ATI Radeon HD 5800". I have connected following to my graphic card:
1*HDMI
1*DisplayPort
2*DVI

Into the "Catalyst Control Center(v.10.2)->Desktop & Displays" I can see all my 4 displays but when I "Create Group..." there is only possible to set-up 2 displays.
Is my DisplayPort-cable to blame for this? This is what I have:

DISPLAYPORT(graphic card) - HDMI(display) 20-PIN HA - HA
(http://www.dustinhome.se/pd_5010329346.aspx)

If it is the cable who is wrong, can I just buy some extra adapter-thing to my hdmi?

 

[tweaked]

the HDMI and a DVI both share a same port, it's either/or not both.

You need an ACTIVE display port adapter.

 

[Hunter_wow]

ok. To be on the safe side I plugged in monitors into all my ports. But you can say I have the following setup to make it more clear:
1*dvi from computer to vga display
1*hdmi from computer to hdmi display
1*diplayPort from computer to hdmi display <- the cable in question

But I guess I still need the displayPort to be active. But to expensive. Will have to wait a year or two to let the prices fal....

 

[SOSUS]

So, you have a 58xx, and four monitors, but can't afford 775SEK for the converter?

 

[Hunter_wow]

Sounds funny ey? Whell, I guess I have to consider it. Thanks for the help.