Eyefinity connection issues

[Finger78]

I have searched for an answer but I cannot seem to locate one pertaining to my particular questions.

I am getting ready to purchase 2x 7970's on 3 monitors and I have some questions as the information I read seems to conflict with one another and there seems to be a fair amount of debate on the matter and I need some clear answers to better make a choice. My video card and monitors are listed at the bottom of the post.

Questions:
1. Does Eyefinity require that I run all 3 monitors from a single card in a dual card setup? I would prefer to run all DVI connections to my three monitors 2x DVI form card 1 and 1x DVI from card 2. If the answer to this question is YES then I would like to know the preferred method of connection.

2. I have read that using at least one Displayport is required but I'm unsure if this also applies to dual card setups, with this comes the question of needing an active adapter to hook up to it. My question is if the card and monitor both have display ports will I still require an active adapter?

I will be making these purchases within the next 48 hours so please give me clear answers to my questions.

XFX Double D FX797GTDFC Radeon HD 7970 GHz Edition 3GB 384-bit GDDR5 PCI Express 3.0 x16 HDCP Ready CrossFireX Support Video Card

Ports
1 x HDMI
2 x Mini DisplayPort
2 x DVI

ASUS VE258Q Black 25" 2ms HDMI LED Backlight Widescreen LCD Monitor w/Display Port & Speakers 250 cd/m2 50,000,000:1 ASCR

Ports
1x D-Sub
1x DVI
1x Displayport
1x HDMI

 

[KingFatty]

For the two questions under item 2., I can answer the second part: No, you won't require an active adapter to run displayport from the video card to a monitor that supports displayport. You just need to use a displayport cable. If the monitor takes full-size displayport, but the card only has a mini displayport, then make sure your cable works with that or use a cheap adapter to convert from mini to full size (may be included with the video card).

 

[Finger78]

Thank you KF, now if I can get a definitive answer on the first question and I can stop freaking out about this issue.

 

[BrightCandle]

Answer to 1 is that yes all connections must go to the first card. The preferred connectivity for dvi users is 2x dvi and the 1 display port into a dp to dvi active adapter and then onwards to your monitor. Almost all 7970s now come packaged with the adapter. Of course since you have a monitor that supports dp you ignore the adapter and just do 2xDVI and 1x DP

 

[KingFatty]

But there are $30 single-link DVI-displayport adapters, whereas if you wan dual-link, it will be more expensive. You'd need dual-link for bigger resolutions like 2560x1440 running DVI. However, if you get a fancy monitor like that, it may likely already come with displayport so a non-issue (check out the Auria 1440p display from microcenter $399).

 

[3DVagabond]

As has been stated, all monitors to one card, the main one, and no you don't need any adapters since your monitors have DP inputs. DP is the preferred connection. I would do 2xDP+1xDVI. Just make sure your DP cables are listed as compliant by AMD. Not all DP cables follow proper compliance and this is where many people run into the "failing to wake from sleep" bug. There's a "return 3v connection" that is not supposed to be active but is in many cables. I'll try and find a proper source to link to.

 

[jackstar7]

To make one small distinction, yes, all 3 go to one card, but that one card does not have to be the card in the first PCIe slot. In my very weird circumstance, I am using the "Secondary" card as my display out card and it works. I don't imagine it will come up for more than a handful of people (ever), but just something to keep in the back of your head just in case.

 

[Finger78]

All great information, thanks for the quick replies.

I do have a few small followup questions though.

The adapter that will "likely" come with the video cards, is it an active or a passive? And does it really matter which one I'll be using since my monitor will be using it's own DP interface. I only ask because I will likely need to use the adapter to convert from the mini-DP interface on the card to the normal size DP of the cable/monitor.

 

[BrightCandle]

The adapter they send out is an active one. It needs to be an active one or it wont work. DVI and DP are different protocols so it has to do a real conversion.

However changing mini DP to DP is absolutely fine to convert with just a physical adapter, it takes no power and does nothing but electrically wire the two sides together. This doesn't need to do any conversion as its the same protocol on both ends (DP) but just a different size socket.