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So, I got a really good deal on a 61" plasma TV that was used (Sony KDE61XBR950) off of craiglists for $450 in amazing shape with no burn in. I currently have two monitors hooked up to my Radeon 6850. First was a 23" DVI LCD, second is a 19" VGA LCD which I need to use a converter to in order to get it to DVI. Apparently only ONE of the two DVI ports on the back of a 6850 (and from what I understand the entire 6xxx series) supports VGA to DVI. You simply can't use the other one, it wont detect it. The one that works is the bottom one.

Now after I got the TV it has a DVI-D port on it I wished to use. I bought a HDMI cable to use the HDMI port on the back of the 6850 and a HDMI to DVI converter. To my dismay I couldn't have the HDMI port active while the top DVI port was active and from what I read they share bandwidth with eachother. That means YOU CANNOT have a HDMI and DVI device plugged at the same time with a VGA device.

...so I went and bought a Displayport to HDMI adapter, which then will be converted to DVI-D at the end (something I had not intended). This did not work either. The top row of ports share bandwidth with each other for some obscene reason and you NEED to purchase a active Displayport to HDMI adapter in order to get any of the above ports to work with two DVI inputs on the other two ports.

Now, what I question is after reading the displayport article on wikipedia, why can't I use a passive adapter? I'm not entirely sure how an active adapter magically enables DVI signals to be sent to a single link device. The TV only requires a single-link DVI connection, which can be provided by Displayport. (They don't even make active HDMI adapters so I don't know how to get two DVI devices to work physically plugged into those ports and an HDMI device. A trait that is shared by the 5xxx series as well.)

According to the article I need only a passive adapter to make it work, yet AMD requires you to use an active adapter... a prospect that seems complete hoghwash. They even have an entire page dedicated to it in which they tell you only two legacy devices work at one time. What exactly qualifies a device as being legacy? Apparently all the ports are legacy unless you buy a overpriced adapter to make it work. You can plug in a maximum of two legacy devices and then you need to start buying expensive adapters. Of course this fails to included that it's impossible to run a HDMI device and two DVI devices without adapters off of the said ports.

It's strange really. After all the testing tech websites have done on this, even TR had their own Eyefinity setup done (hell I even read the article), they failed to mention you need to start buying $30 adapters to add extra monitors once you reach a certain point. Interesting in itself, if AMD went to such lengths to do the setups could they have been trying to mask this?

It really is quite honestly a huge chore when I have a typical setup for most people. Most users I will guess are using a crappy VGA or DVI monitor as their secondary (used or procured) and a good DVI LCD as their primary, which is exactly what I'm doing. And exactly as I am doing, most users will be adding a TV through HDMI or HDMI to DVI as displayport isn't nearly as well adopter as either DVI or HDMI. Coincidentally this combination can't even be done.

I am rather pissed off myself as I am going on about three weeks of shipping items around only to find out I once again got the wrong item. I wish TR would've mentioned something about this.

/end rant

Page I talked about for reference: http://support.amd.com/us/eyefinity/Pag ... ngles.aspx

It's a shame you didn't find the Eyefinity FAQ page on the AMD site before you started setting things up since this highlights the exact issue you're describing. Essentially Eyefinity can only support more than two displays if you use native DP or an active DP adaptor for the third display. It's also here on the 6850 footnotes page on the AMD site. It's fair to say this information isn't on the front page in big flashing lights, but it's not entirely hidden either.

TR did mention this in the 5870 review as well, though in fairness they made no mention of active vs passive adaptors:

TR wrote:

Most members of the Evergreen family (with the exception of the smallest chip) will be able to support up to three different displays simultaneously, as the 5870 can with its four outputs. One may connect either two DVI displays and one DisplayPort or one DVI, one HDMI 1.3a, and one DisplayPort.

Yeah, I have a 6850 though and I wish to do extended desktops, not Eyefinity... the details are rather hidden. It was sort of hinted on in the Eyefinity test setup on TR

All of those adapters are of the passive variety, which means they're simple plug converters. That's fine for most uses, but the DVI and HDMI connectors are limited to a peak resolution of 1920x1200. If you want to drive a higher resolution display off this card via HDMI or dual-link DVI, you'll need an active converter, which is a more expensive proposition. AMD keeps a list of Mini DisplayPort adapters it has validated for use with Eyefinity,

The quote states higher resolutions then 1920x1200... I don't want to do higher then that, just 1920x1080... which a passive DP to DVI adapter should be able to do without being active.

However, that may or may not apply to Eyefinity... the AMD page does not note extended desktops or even clone desktops, just Eyefinity nor does the tests here at TR.

This is putting aside that none of the sites state that you can't run two DVI devices and a HDMI device at the same time using the physical ports, no adapters... putting aside the two DPs.

The vague bit from their Eyefinity website:

Connectivity Requirements: AMD Eyefinity technology is supported by graphics cards in the ATI Radeon™ HD 5400 series and higher. These cards can support up to six monitors (depending on the model), subject to the following restrictions:
• A maximum of 2 legacy monitors (VGA, DVI or HDMI) can be enabled simultaneously, provided that each monitor is connected either directly or via a “passive” DisplayPort™ adapter/dongle. “Passive” adapters/dongles will NOT support more than 2 legacy monitors.
• To enable support for more than 2 monitors, “active” DisplayPort™ adapters/dongles are required (or monitors with direct DisplayPort™ connectivity must be used).
• Approved “active” adapters have no general connectivity restrictions with AMD Eyefinity technology.

As I stated in my original post, what exactly defines 'legacy monitors'? Two DP monitors and any of the above 'legacy' monitors does not work with passive adapters either, so I don't even know why they exclude them. It still eludes me why an active adapter is even needed to get past this 'legacy' restriction, which obviously has some logical flaws to it. I can understand a HDMI and DVI port sharing bandwidth (which they never tell you about), but DP standards only require an active adapter if you have higher then a 1920x1200 resolution or need a dual-link DVI port.

To start the conspiracy wheels turning, this seems like a partnering scheme to make people buy overpriced active adapters that bear the Eyefinity gold standard. For instance, if you could use the HDMI port and the two DVI ports at the same time you wouldn't even need to buy an active adapter.

*edited for clarity*

The problem does not really lie in the ports themselves, but where the signals for each port come from. DisplayPort supports fall back to single link DVI using a simple passive adapter. The hardware that generates the DVI signals for each of the DVI ports is the same hardware used to generate the DVI signals output on the DP port in legacy mode. In legacy mode the DP port pins are simply connected to the appropriate signals from the DVI outputs, meaning you can't use both to output different signals.

Yes, it's confusing. I don't know why they did it that way. Some combination of engineering limitations and cost and desire for marketing specs, I'm sure.

I'm not sure why you're still confused. The Eyefinity FAQs clearly state that this is all to do with clock signal generation. The cards only produce three clock signals: two for legacy ports (VGA, DVI, or HDMI) and one for DisplayPort. The DisplayPort clock signal can drive multiple monitors, but the legacy clocks cannot, and any passive DP adaptors use one of the legacy clock signals.

AMD wrote:

Why do you need DisplayPort?

AMD Eyefinity technology leverages DisplayPort and its ability to easily scale to drive multiple displays from a single clock source.
What's the difference between active DisplayPort dongles and passive DisplayPort dongles?

Passive dongles use the DisplayPort connection to receive non-DP signaling from the connector and they 'passively' adjust the signals to be compliant with the connected monitor. Passive dongles are considered legacy connections, not DisplayPort connections, therefore they do not fulfill the DisplayPort connection requirement mentioned previously and cannot be used to enable 3 or more displays. They do, however, offer an affordable solution to adapt legacy displays to DisplayPort connections.

Active dongles use true DisplayPort signaling to 'actively' translate and re-transmit the signals as the required outputs. Because they use the true DisplayPort signaling, they are considered a DisplayPort connection and meet the requirements to enable 3 or more displays.

DisplayPort to DL-DVI dongles require an external power supply which is usually through a separate USB connection (the USB connection must meet the USB 'high power' specification).

How many non-DisplayPort monitors can I use with an AMD Eyefinity technology-enabled graphics card?

You can connect up to two non-DisplayPort monitors at one time to an AMD Eyefinity technology-enabled graphics card using non-DisplayPort connections or passive DisplayPort dongles. To enable and drive 3 or more non-DisplayPort monitors at one time, the additional non-DisplayPort monitors must be connected with an active DisplayPort dongle.

I'm not sure where the conspiracy theory comes in. This is a technical limitation because they made the decision not to support more than two legacy connections, presumably for cost reasons. Why raise the cost of your product for something that 90%+ of your customers are unlikely to require? They probably also reasoned that anyone with the funds to run three monitors wouldn't get too upset about the cost of an active DP adaptor (less than £15 over here including tax for Sapphire and XFX single-link DVI adaptors, so I'd be surprised if you can't find them for less than $25 in the States).

A passive DisplayPort to DVI adapter will only work if the port is a "Dual Mode DisplayPort", meaning the manufacturer has chosen to hook a TMDS transmitter into the DisplayPort's aux channel. As you've discovered, though, the 6850 only has two TMDS transmitters, and one is shared between a DVI port and the HDMI port.

That's why you need an active adapter to connect a DVI monitor to the DisplayPort.

Ugh. Sorry you ran into problems. Our coverage was never intended as a comprehensive guide to setting up your own Eyefinity setup, and we certainly didn't spend any time trying to set one up with a VGA output in the mix. We have, however, talked about the issues with various adapters and about our own lack of experience with them. See here, for instance:

http://techreport.com/discussions.x/19551

The trouble with that solution is that the dongles themselves haven't been great. The best ones can cost over 100 bucks a pop, and the less expensive passive-type adapters have apparently been troublesome, with compatibility issues and the like. I say "apparently" because our experience with Eyefinity has been limited to monitors with DisplayPort inputs, so we haven't had the particular joy of dealing with the flickering screens or HDCP problems potentially caused by cheap dongles.

Tried to be up-front about things. I sure didn't intend to mislead about the potential for problems with legacy displays and mixed input types!

I'm not genuinely confused as to what I am or am not capable of doing with the card anymore, rather pissed off that it would be cheaper for me to get a low budget card and put it in another slot then use three monitors with my original card. Something I see as very inflammatory considering all the extra ports they tacked onto the card to make it seem a lot more then it really is. To add insult to injury I could drive three displays with my 4870... More so none of these limitations were really outlined anywhere visible without having the problem first, then all of a sudden I have google results and forum posts.

I'm not trying to do anything as high-test or awe-inducing as Eyefinity either. I simply wanted two extended desktops, one of which I could play my movies on for my big screen TV, the other I use as a second monitor.


It's hard to imagine a majority of users not running into the same problems I just have. Most people aren't going to run out and buy three brand new monitors with displayports on them. Like I said, they probably have an older monitor they use as a secondary one (which will more then likely be VGA), a nice one they use as a primary monitor, and then a TV or possibly a third crappy monitor on the other side.

Bensam123 wrote:

It's hard to imagine a majority of users not running into the same problems I just have. Most people aren't going to run out and buy three brand new monitors with displayports on them.

Most people don't even have two monitors, let alone three.

I meant out of the people who would be sporting more then two monitors or even two monitors. Classic setup is using one of the older monitors you outdated with a new monitor as a secondary instead of getting rid of it.

I understand your frustration, I had the same issue with 2 samsung lcds and a samsung led tv. I tried every possible way to get all three devices to play nice but wasn't going to happen. I took the view of that situation that I have a unique setup and the video card wasn't build for that in mind.

So long story short I just ended up build an entertainment system for the tv. I know its some what a luxury but I had spare parts and didn't cost too much.

Sorry you got burned by this, but AMD's page is pretty clear about the limitations for multiple displays on Eyefinity-capable cards (also, Eyefinity is any AMD-GPU setup involving more than 1 screen, not just surround-gaming and video wall type stuff, it's just a brand name AMD have slapped on it). I very much doubt it's a conspiracy or they're "not telling you it", as it's right there on the page. As SecretSquirrel said, I'm sure it's just a cost-saving measure, as it's safe to say that 90% of customers will never run 3+ monitors from one of the cards, and chances are that those that do professionally (stock market brokers, etcetc) won't balk at adding $30 per extra monitor.

Then why do they have five fricking outputs on the back of the card? I don't know, I suppose I thought I could use the HDMI one and the DVI one... who knew you can't actually use both of them at the same time or you can't use both DVI ports with VGA monitors? It doesn't state that anywhere. Matter of a fact according to the compatibility page for Eyefinity VGA monitors are considered 'legacy' and you can use two at the same time... but you can't. The top DVI port can't output to a VGA monitor.

"pretty clear" wouldn't mislead people. I mean how many people expect there to be perfectly useless ports on the back of a $300 card?

Sorry about your woes. For a while, Sapphire was offering a 3-Eyefinity card that had an extra DAQ (I may not be using the exact correct terminology), so you could run 3 monitors where none were native DisplayPort, just a mix of DVI/VGA.

I agree in some sense that the 6xxx series was falsely "ready for the future" in supporting DP, where very few DP monitors have been sold; however from a marketing standpoint and the ability to do 6-way Eye really required DP support. I can imagine how much more money the 6-way cards would have been, had they had 3-4 more DAQ's to support 6-way in a DVI/VGA legacy support setup.

Anyhow, I have found that the HydraGrid setup where you can snap windows into place on an individual monitor is more useful than the general Windows extended desktop. I generally don't like floating Windows, unless they are just dialog boxes or some such thing.

My setup is: 3xDVI monitors, 1 DVI/DVI cable, one HDMI/DVI cable, one $30 active DP/DVI 'active adapter' to DVI/DVI cable. There are reports of people using passive adapters successfully, but they seem like they come with a lot of limitations. From my reading, TR and "official" AMD claptrap, I elected to stay away from any sort of VGA cabling altogether - it seemed like a road that led to disappointment. I also did not pull the trigger on 3 way Eye until after the 6xxx series was released, as there were bugs still being worked out.

just brew it! wrote:

Most people don't even have two monitors, let alone three.

Indeed, their prior mainstream IGPs (Llano may have fixed this; I'm not sure) couldn't even drive two digital displays at once - one had to be VGA.

One of the A75 motherboards that I checked supports either HDMI + D-sub (analog) or HDMI + DVI-D, so you can drive two digital monitors at once, but one of them must be HDMI or use an HDMI-to-DVI cable (very cheap and easy to find).

insulin_junkie72 wrote:

just brew it! wrote:

Most people don't even have two monitors, let alone three.

Indeed, their prior mainstream IGPs (Llano may have fixed this; I'm not sure) couldn't even drive two digital displays at once - one had to be VGA.

Yes, this is actually *my* pet peeve. I'd love to be able to drive two DVI monitors without having to buy a discrete GPU, especially given that the choices for passively cooled discrete GPUs with dual DVI are slim to non-existent.

just brew it! wrote:

Yes, this is actually *my* pet peeve. I'd love to be able to drive two DVI monitors without having to buy a discrete GPU, especially given that the choices for passively cooled discrete GPUs with dual DVI are slim to non-existent.

Check out OEM's. Dell sells a lot that are geared for business. Here are two right here

http://accessories.us.dell.com/sna/prod ... e_irrank=0
http://accessories.us.dell.com/sna/prod ... e_irrank=0

and that was after 2 pages donig a quick search for "ATI"


And back on topic, sucks you got burned. But it is your fault for not checking compatibility first.

LaChupacabra wrote:

just brew it! wrote:

Yes, this is actually *my* pet peeve. I'd love to be able to drive two DVI monitors without having to buy a discrete GPU, especially given that the choices for passively cooled discrete GPUs with dual DVI are slim to non-existent.

Check out OEM's. Dell sells a lot that are geared for business. Here are two right here

http://accessories.us.dell.com/sna/prod ... e_irrank=0
http://accessories.us.dell.com/sna/prod ... e_irrank=0

and that was after 2 pages donig a quick search for "ATI"

First one is "classic" PCI (not PCIe), and only a Radeon 9250; while gaming is very low down on my list of priorities these days, a 10 year old GPU is still lower than I'm willing to go.

Second one looks reasonable.

I'd still rather be able to do it with a (modern) IGP; and even an IGP would kick that Radeon 9250's butt.

I thought that you always needed "active" DP adapters. Passive DP adapters are a crapshot at best.

My Z68 board is currently driving two monitors, one off DVI and one off HDMI, no issues. A Crossfire pair is driving three more; also, I have not installed Lucid's software*.

*The Virtu software seems designed for people that want to use both GPUs with one monitor, with the ability to switch between which is primary, and isn't needed if you're using separate displays for each GPU.

JustAnEngineer wrote:

One of the A75 motherboards that I checked supports either HDMI + D-sub (analog) or HDMI + DVI-D, so you can drive two digital monitors at once, but one of them must be HDMI or use an HDMI-to-DVI cable (very cheap and easy to find).

Essentially this.

Airmantharp wrote:

My Z68 board is currently driving two monitors, one off DVI and one off HDMI, no issues. A Crossfire pair is driving three more; also, I have not installed Lucid's software*.

Yeah, the no-dual-DVI-with-IGP issue seems to be specific to ATI's IGPs.

Yeah and my 4870 can do two DVI or DVI-VGA monitors at the same time AND a component TV *grumbles*.

On the topic of other choices, I had considered making a media PC (around $200 at least and another computer running), a VGA converter as my laptop only has a VGA out (round $60 and not ideal as it would tie up my laptop), a media player which wouldn't have long term support for $100, or a USB to DVI dongle... which may or may not worked. I looked at some ones that were pretty bad at being choppy and one that sounded pretty good, but still another crapshot.

As it stands I will be going mini-DP to DVI > DVI to HDMI > HDMI cable > HDMI to DVI. They don't sell active DP to HDMI adapters... wonder why... (XD).

Welp to add a bit more to this, I finally got my active adapter and it works fine now... $50 later of course.

Sorta interesting to throw more fuel on the fire. You can't buy an active mini-DP or DP to HDMI adapter. I had to purchase a mini-DP to DVI and a DVI to HDMI adapter. There was just a story on Slashdot about the people who made HDMI suing makers of HDMI to DP interfaces because it 'violates' their interface standard. Interesting tid bit.

Well, HDMI was meant to be a next-generation A/V interface. It was never meant to go with computers, the only reason video cards have them is for HTPC systems. The mess start back in 2005, LCD manfacturers were making displays for both computer and HDTV customers. It is cheaper for LCD manfactuers a standard line with both interfaces, instead two seperate lines with exclusive support.

Eventually, DP came around and provided all of the benefits of HDMI and more (royality free!)

Now, LCD manfactuers are starting to make HDMI exclusive to HDTV displays while computer displays are being paried up with DP. The royality costs for HDMI justify having seperate production lines.

Thanks for having this conversation guys. I was having the exact same problem but didn't realise. I bought a Dell XPS xxxx with a 6670. No DisplayPort, but a DVI, VGA and HDMI. Any two screens would work but I couldn't never get the third up simultaneously.
I read the bit about needing to use DisplayPort for the 3rd monitor, and so went and bought a Sapphire 6770 with HDMI, DP and DVI. Still didn't work, and now I know why.

It's very confusing, and for the high-and-mighty's that say "well derr! you should have researched it first - how can one know that one needs to research something first until there's a problem? Like the OP, I just saw 3 ports and thought - great, 3 monitors!!

anyway, no doubt when I ditch the passive DP adapter and get an active one it'll all work great.

thanks again

P.S Hope no-one minds the thread necro!

It REALLY gets annoying when you go out an buy a AMD listed $30 Accell Ultra AV adapter (Frys) emblazoned with the "ATI Eyefinity Multi-display validated" logo and it STILL won't work. Turns out it was the passive one B086B-001B instead of the B087B-005B active...

Apparently the "ATI Eyefinity Multi-display validated" logo only means it plugs in. and works with one or 2 monitors... NOT 3.

It actually DOES bring up all 3 displays using the radeonfb under Linux, but that's not exactly what I had in mind.
(it DID work fine after some thrashing with 2 displays and the MBs 6200 for the third, but no 3D as Xinerama had to be enabled)

I picked up the DP to HDMI adapter, which THEN converts to DVI, wondering If I need to stick with DP>DVI version.

All 3 monitors are 1680x1050 native, DVI or VGA.

The CORRECT active one was $2 more from Amazon w/free shipping.
(at least Frys has an easy return policy, too bad they don't carry the right stuff)

It gets even more annoying when you finally jump through all the hoops and it still doesn't work...

I bought a AMD certified gold active adapter, and the driver uses the DP and the DVI out..
It's oblivious to the middle HDMI monitor/connection now.

Installed Win7 --Installed Catalyst drivers (latest) STILL only 2 displays detected.

So I have the active displayport adapter, what exactly is the trick here?

Is there some caveat buried somewhere in the documentation?

I have no advanced technical knowledge of computers. I am using an AMD 6800. No problem running two monitors. I thought it would be no big deal to use the additional port and hook it to my HD 1080p TV (to just watch videos and such). As I am not a computer genius, I thought I was missing something. Several weeks, adaptors, searches, and migraines later, I'm glad I found this posting.

Thread necro.