Anybody running 3x 30" LCDs with two Apple miniDP to DVI adapters?

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three4seven

[H]ard|Gawd
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I'm trying to run three 30" LCDs on one 6950 1gb (not for gaming) that use dual link DVI inputs.

I ended up buying two Apple miniDP to dual link DVI adapters and used the native dual link DVI connection to connect the three monitors.

Here's my issue - no matter what I do - I can only get two monitors to work at once.

I've tried every combination to test if it was an issue with the mini DP adapters.. or my monitor... or cables... or my 6950. Everything seems fine independently from what I can tell. The only thing I've come up with is that I cannot use both mini DP to dual link DVI cables at the same time. It only works if I use one Dual link DVI (native) and one miniDP.

When I add the second miniDP adapter, all the monitors aren't detected correctly - can't use native resolution and become detected as "mobile PC displays'.

I tried hooking it up to another system with 6950 2gb setup - and the same issue occurred. However, if I kept hitting "detect" (in windows 7 "screen resolution"), it would eventually run all three monitors at native resolution. Upon restarting however, I would have to go through all of it again to get it to work. Tried the same method and can't get it to work on the 6950 1gb - even using the "detect" method.

Just seeing if anyone has any experience with two apple miniDP adapters simultaenously and if they experienced the same issues.

----

Update: Seems I can get it to work by using the detect method to get two miniDP to work at the same time without the native dual link dvi plugged in..

Second observation: I was finally able to get all three screens to work by plugging both USB connectors into an external USB charging hub that powers on the two USB cables from the adapters at the same time.

That said, it doesn't restart properly. As soon as you shut down, you have to go through the whole process again - unplugging the USB power cables from the miniDP and then back into the usb charger... and they must power on at the same time....
 
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I use 3 of them with 3 x 30" monitors. These are the worse things I've ever used. Here's how I get mine to work.

1. I use the powered HUBs on the monitors to power the Adapters. This requires connecting the usb cable to the computer, to the hub and from the hub to the adapter (using a usb extension of curse). I do this for every monitor. Which requires way to many cables, but that's another story.

2. On top of that I have to boot each monitor up in an order that my computer likes. Currently it's middle, right, left. And I have to wait for the computer fully recognize something plugged, so no doing this fast.

3. Reboots are impossible to do with all monitors connected..electrically that is. So I just leave the middle one on, then turn the other two later. If the monitors isn't ON it isn't connected. So that works well.

4. If I want to connect another monitor (I have a 2007fp I use sometimes) using the passive dvi dongle or in your case the built in dvi, I have to plug in the active adapters FIRST than the passive dvi monitor. This require me unplugging the 2007fp after every reboot, or anytime I kill the group by disconnecting the other monitors. Annoying.

5. If anything goes wrong with these adapters, generally a power cycle (unplug power then replug) will fix it.

Hope this helped, I've been dealing with these issues ever since I bought my 30" and all I have was miniDP on my card. I wish there was a good gaming card that could take at least 2 of these adapters away. I can deal with one of these shitty adapters.
 
Didn't like the advice I gave in the other thread? It is probably going to be the easiest route to go. You could have almost bought the card for the price of your two adapters. It will work out of the box.


Edit: Not as a good deal as previous one but still not too bad considering the premium these cards carry. Link.
 
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Same issue, 2 apple adapters, 120hz, almost went insane, removed one adapter, set up eyefinity with 2 screens dvi/apple adapter, then as that worked with eyefinity, then I added the 3 screen, and then I made it work.

did reinstall windows which made this a major headache, replaced the other older screens earlier I had and had no issue at all setting it up with 120hz and adapters then but now, oh boy.
 
morgwon said:
Didn't like the advice I gave in the other thread? It is probably going to be the easiest route to go. You could have almost bought the card for the price of your two adapters. It will work out of the box.


Edit: Not as a good deal as previous one but still not too bad considering the premium these cards carry. Link.
Click to expand...

Sorry if it seemed like I didn't take your advice. I actually used to have that card, but sold it when I purchased an x58 with three pci-e slots. It made sense to buy three cheap cards versus one expensive one - at a fraction of the price and performed the same if not better. One card crapped out unfortunately and spurred my desire to buy a single card again.

So - the reason why I didn't consider that card again? I just felt like it was a bad value. For $250 + $10 for each cable/adapter, it would be an expensive card that is pretty underpowered. The card is more geared toward mobos with very limited PCI-e cards. I figured I'd pickup a 6850 in the $100 range - and pickup two adapters. I considered the adapters as "reusable" as it meant I could use the 30" LCDs on my laptop as well. And even then - at each adapter costing around $50 each, that'd still be under the cost of an NVS 450, and be way more powerful. Yes, it's not a gaming machine, but I figure might as well try to get the best bang for the buck. And honestly - I had no idea it would be this complicated

In the end, I think I'm going back to my three cheap card setup. Seems the most cost efficient without any of the complicated setup issues with mini displayport to dual link DVI adapters
 
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suiken_2mieu said:
I use 3 of them with 3 x 30" monitors. These are the worse things I've ever used. Here's how I get mine to work.

1. I use the powered HUBs on the monitors to power the Adapters. This requires connecting the usb cable to the computer, to the hub and from the hub to the adapter (using a usb extension of curse). I do this for every monitor. Which requires way to many cables, but that's another story.

2. On top of that I have to boot each monitor up in an order that my computer likes. Currently it's middle, right, left. And I have to wait for the computer fully recognize something plugged, so no doing this fast.

3. Reboots are impossible to do with all monitors connected..electrically that is. So I just leave the middle one on, then turn the other two later. If the monitors isn't ON it isn't connected. So that works well.

4. If I want to connect another monitor (I have a 2007fp I use sometimes) using the passive dvi dongle or in your case the built in dvi, I have to plug in the active adapters FIRST than the passive dvi monitor. This require me unplugging the 2007fp after every reboot, or anytime I kill the group by disconnecting the other monitors. Annoying.

5. If anything goes wrong with these adapters, generally a power cycle (unplug power then replug) will fix it.

Hope this helped, I've been dealing with these issues ever since I bought my 30" and all I have was miniDP on my card. I wish there was a good gaming card that could take at least 2 of these adapters away. I can deal with one of these shitty adapters.
Click to expand...

I feel your pain now and regret going the miniDP to dual link DVI route. Had I know it would be so troublesome - I wouldn't have bothered. If I could fix everything with a simple power cycle - that wouldn't even be so bad... but my setup apparently requires for the two displayport monitors to powercycle at the same time... otherwise one monitor won't be detected correctly.

And even THAT is okay - the deal breaker for me is that if I put files, folders, icons, etc on the other screens, when the power cycles, it all gets messed up and gets put back on one screen. Drives me crazy and makes it totally not worth it.

I don't see it as a total waste though - always wanted to use the 30" LCDs with my laptop though - and now I can with the adapter.
 
hajalie24 said:
Umm, why does everyone seem to forget that the cards have hdmi 1.4?
Click to expand...

AMD graphics cards can only support one non-DP device so for 3
screens you'd have to use two DP outputs.

While the cards support HDMI 1.4 I'm betting the monitors dont.
HDMI & DVI are almost the same but they're not always interchangable.
When DVI needed to support higher resolutions they used a second link.
HDMI supports higher resolutions by increasing the bandwidth on a single link.
 
three4seven said:
Sorry if it seemed like I didn't take your advice. I actually used to have that card, but sold it when I purchased an x58 with three pci-e slots. It made sense to buy three cheap cards versus one expensive one - at a fraction of the price and performed the same if not better. One card crapped out unfortunately and spurred my desire to buy a single card again.

So - the reason why I didn't consider that card again? I just felt like it was a bad value. For $250 + $10 for each cable/adapter, it would be an expensive card that is pretty underpowered. The card is more geared toward mobos with very limited PCI-e cards. I figured I'd pickup a 6850 in the $100 range - and pickup two adapters. I considered the adapters as "reusable" as it meant I could use the 30" LCDs on my laptop as well. And even then - at each adapter costing around $50 each, that'd still be under the cost of an NVS 450, and be way more powerful. Yes, it's not a gaming machine, but I figure might as well try to get the best bang for the buck. And honestly - I had no idea it would be this complicated

In the end, I think I'm going back to my three cheap card setup. Seems the most cost efficient without any of the complicated setup issues with mini displayport to dual link DVI adapters
Click to expand...

Ah. Yeah it does carry a price premium so you can have everything working out of the box. I did the same thing at work. I ended up going two el cheapo nvs cards rather than getting an nvs 450. Well good luck whatever route you end up going.
 
Tak Ne said:
AMD graphics cards can only support one non-DP device so for 3
screens you'd have to use two DP outputs.

While the cards support HDMI 1.4 I'm betting the monitors dont.
HDMI & DVI are almost the same but they're not always interchangable.
When DVI needed to support higher resolutions they used a second link.
HDMI supports higher resolutions by increasing the bandwidth on a single link.
Click to expand...

No, they support 2. And there's adapters (much cheaper than $100) that convert hdmi 1.4 to dual link dvi.
 
hajalie24 said:
Umm, why does everyone seem to forget that the cards have hdmi 1.4?
Click to expand...

Because that's not going to work, you need a HDMI 1.4 type B which hasn't been used on any products to have HDMI to Dual Link DVI. It has 29 pins vs HDMI Type A's 19 pins.
 
Just tried it with 2 different hdmi to dual link DVI dongles and 1 HDMI to dual link cable

Neither could handle the 2560x1600 resolution.

We can put that theory to rest now.
 
three4seven said:
Just tried it with 2 different hdmi to dual link DVI dongles and 1 HDMI to dual link cable

Neither could handle the 2560x1600 resolution.

We can put that theory to rest now.
Click to expand...

Because HDMI has a single TMDS signal, while DL DVI has two. HDMI can do higher resolutions because of higher clocks, but your monitor has to natively support HDMI 1.3+.
 
iconiK said:
Because HDMI has a single TMDS signal, while DL DVI has two. HDMI can do higher resolutions because of higher clocks, but your monitor has to natively support HDMI 1.3+.
Click to expand...

I am fully aware that HDMI 1.4 can natively display resolutions greater than 2560x1600 - however, I was almost sure the "cheap" HDMI to dual link DVI dongles/cable referred to by the other poster are currently unable to support that resolution. I therefore tested it.
 
three4seven said:
I am fully aware that HDMI 1.4 can natively display resolutions greater than 2560x1600 - however, I was almost sure the "cheap" HDMI to dual link DVI dongles/cable referred to by the other poster are currently unable to support that resolution. I therefore tested it.
Click to expand...

Yeah, cause there's no way to get DL DVI out of HDMI without a chip to generate two slow TMDS signals from a fast TMDS signal.
 
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