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How do I setup Eyefinity to support three monitors on a Radeon HD 5770 card? Currently I can setup only two at once in any combination.

Monitors are connected as DVI-DVI-HDMI.

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up vote 13 down vote accepted

On AMD Eyefinity Technology, there is this remark at the bottom:

Driver version 8.66 (Catalyst 9.10) or above is required to support ATI Eyefinity technology and to enable a third display you require one panel with a DisplayPort connector.

Do you have one screen connected with DisplayPort?

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Arrgh. Thats the catch! Well I do not have DisplayPort monitor. But I am going to the local shop for DisplayPort to HDMI adapter. – Peter Stegnar Nov 6 '09 at 11:13
I have still problems: now I have DVI-DVI-DP and still drivers do not allow to have three monitors. What to do? – Peter Stegnar Nov 6 '09 at 12:31
Hehe you forgot about getting a new DP display. =) Dell UltraSharp series are quite ok. – Shiki Jun 16 '10 at 6:35
@Peter First make sure that it's an active DP->HDMI adapter. If it is, then you may need to use both display ports instead of only one. This page has more info on Eyefinity connectivity. – Ben Richards Sep 9 '11 at 17:28

This cannot be solved with a passive adapter. Issue is in hardware and comes down to signaling on DVI, HDMI and DisplayPort.

If I recall correctly DVI and HDMI require an own clock signal per output. Because DisplayPort is a package protocol it requires only one clock signal per card. ATI Radeon HD 5000-series has two clocks for DVI/HDMI so it is possible only to use 2 of those devices, adapters do not change this fact.

There is however an active adater, that allows you to transform DisplayPort signal to DVI-signal. More information about the device here

So what you need is a native DisplayPort monitor or an active device that transforms DisplayPort signal to DVI/HDMI.

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Your explanation is correct, but the initial comment is not. It can be solved with an adapter, but you need an active adapter that will use the clock signal from the DisplayPort. – Jeff Davis Apr 22 '10 at 15:22
I should have used word passive in first paragraph (now added). Active adapter is however mentioned in third paragraph. – Ahe Apr 27 '10 at 6:16
I'd add to this that if you want to get the third monitor working on the cheap you CAN use a Displayport-VGA passive adapter, and it'll work fine (as I've just found out). I'm assuming from Ahe's answer that trying to do a DVIx3 from a HD 5770 card will require an active adapter. – GordonB Aug 16 '10 at 13:57
I've used a passive adapter on my ATI card and it worked fine with 3 displays, so perhaps they've made some updates to make this possible? – nhinkle Mar 30 '13 at 1:35

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protected by Jeff Atwood Jun 7 '10 at 6:59

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