LordJuanlo
New member
Jim, you said that on the GeForce cards you got strange results when measuring pin 20, can you tell us more about that? I'm curious to know if nVidia implemented some kind of "pin 20 hardware protection" on their cards.
Display Port Cable Issues
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caveman-jim
New member
Ichneumon, I tweeted monoprice about their certification the other day:
FWIW, one of the three cables I tested was from monoprice, bought about a year ago (6' DP-DP cable), it has pin20 connected.
LordJuanlo, not much more to say other than as in the article, I think NVIDIA discovered this problem and engineered their cards to handle it. I suspect this because of the drain of voltage to zero in a cyclical manner, that sounds like circuitry to handle this specific circumstance which is out of specification. It might however be a byproduct of another feature of the card, which just happens to be serendipitous for this circumstance. Whether or not this makes a difference to how it handles Surround I don't know yet.
@cavemanjim: Hey @monoprice are your DisplayPort cables @VESADisplayPort certified or do you plan to submit them for testing?
@monoprice: @cavemanjim Our DisplayPort cables have 1.1 certification and we are working on the newly released 1.2 certs that were recently announced.
@cavemanjim: @monoprice displayport 1.2 was ann. jan 7, 2010. http://t.co/apYAMzbG >3 years ago is 'recently announced'? or did you mean newer std?
@monoprice: @cavemanjim Sorry about that. We are 1.2 and working on “dual mode 1.1”
@cavemanjim: @monoprice great! thanks for the info. Any reason why your cables aren't listed on VESA DisplayPort's website?
@monoprice: @cavemanjim Our certifications are currently through our manufacturing partners but we are working to add our name to the DP database.
FWIW, one of the three cables I tested was from monoprice, bought about a year ago (6' DP-DP cable), it has pin20 connected.
LordJuanlo, not much more to say other than as in the article, I think NVIDIA discovered this problem and engineered their cards to handle it. I suspect this because of the drain of voltage to zero in a cyclical manner, that sounds like circuitry to handle this specific circumstance which is out of specification. It might however be a byproduct of another feature of the card, which just happens to be serendipitous for this circumstance. Whether or not this makes a difference to how it handles Surround I don't know yet.
have a couple of these on the way from monoprice.
LordJuanlo
New member
It looks like they still don't have any 1.2 compliant DP to DP or mDP to DP cables... arghhh... 1 year suffering the X79 issue and now this 
caveman-jim
New member
AFAIK, HDMI doesn't have capabilities to send power from the display back down the cable, so there shouldn't be an issue with this DP-HDMI cable (other than the standard AMD restrictions, you won't be able to use 2 mDP-HDMI cables with your cards other DVI or HDMI outputs, only two 'legacy' displays can be connected at a time).
Treeckcold57
New member
http://www.youtube.com/watch?v=CV-U50Viv_k
There is the MST Hub at 4:00. They said we might see these in 1 to 2 months. (Youtube Caption Closed is probably not so clear to me since it's still in beta).
There is the MST Hub at 4:00. They said we might see these in 1 to 2 months. (Youtube Caption Closed is probably not so clear to me since it's still in beta).
Quick update, I'm still having issues with one of my displays dropping down to 640x480 after waking from sleep. 
Still havn't found a pair of pliers small enough to reach in and pull the pin out. Once I am able to do that I will remove the pin altogether and try again.
Still havn't found a pair of pliers small enough to reach in and pull the pin out. Once I am able to do that I will remove the pin altogether and try again.
Ok.. time for an update..
So I finally received the accell cables from Amazon UK ($68 delivered, compared to $145 delivered if I bought them in Australia!, I sh!t you not)..
Anyway, I hooked them up just like I did to test the previous 17? cables.. One end is plugged into the monitor.. the other end is plugged into a Displayport to mini displayport adapter, as supplied by HIS so that I could plug it into my mini displayport on a HIS 7970. Connected the red tip from the multimeter to pin 20 on the back of the vid card, and the black pin onto a screw.
To my surprise, the multimeter showed up as 3.22 volts.. WTF... seriously.. WTF.. Didn't make any sense.. So I then thought, hrm.. what if I just test pin 20 on the displayport cable, sans adapter.. Stuck the red pin into pin 20 and the black pin on the metal casing. Wow.. 0.00 volts.. wtf.. so I then put the mini displayport to displayport adapter back on, but not connecting it to the vid card, and connected it to pin 20.. 3.22 volts.. WTF.. how is the adapter giving it 3.22 volts?
So yes, the belkin cables show as 0 volts.. the accell cables show 0 volts.. So I dunno how many of the previous cables were also VESA compliant.
Just to clarify, as I have no idea on multimeters, these are the settings I used when testing. I just kept turning the dial until I got a 3.2 volt which I figured must be the correct setting.
I can't test plugging the displayport cable directly into my main 7970 ASUS DCUII as it has a backplate that I cannot remove.
So I finally received the accell cables from Amazon UK ($68 delivered, compared to $145 delivered if I bought them in Australia!, I sh!t you not)..
Anyway, I hooked them up just like I did to test the previous 17? cables.. One end is plugged into the monitor.. the other end is plugged into a Displayport to mini displayport adapter, as supplied by HIS so that I could plug it into my mini displayport on a HIS 7970. Connected the red tip from the multimeter to pin 20 on the back of the vid card, and the black pin onto a screw.
To my surprise, the multimeter showed up as 3.22 volts.. WTF... seriously.. WTF.. Didn't make any sense.. So I then thought, hrm.. what if I just test pin 20 on the displayport cable, sans adapter.. Stuck the red pin into pin 20 and the black pin on the metal casing. Wow.. 0.00 volts.. wtf.. so I then put the mini displayport to displayport adapter back on, but not connecting it to the vid card, and connected it to pin 20.. 3.22 volts.. WTF.. how is the adapter giving it 3.22 volts?
So yes, the belkin cables show as 0 volts.. the accell cables show 0 volts.. So I dunno how many of the previous cables were also VESA compliant.
Just to clarify, as I have no idea on multimeters, these are the settings I used when testing. I just kept turning the dial until I got a 3.2 volt which I figured must be the correct setting.
I can't test plugging the displayport cable directly into my main 7970 ASUS DCUII as it has a backplate that I cannot remove.
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caveman-jim
New member
Just so I'm clear, you're connecting the display port cable to the monitor, and when you measure on Pin 20 you get 0 volts. Then when you add the DP to mDP adapter, you're getting voltage on pin 20?
I don't understand how that's possible unless you're not checking the correct pin on the full DP cable.
Just so I'm clear, you're connecting the display port cable to the monitor, and when you measure on Pin 20 you get 0 volts. Then when you add the DP to mDP adapter, you're getting voltage on pin 20?
I don't understand how that's possible unless you're not checking the correct pin on the full DP cable.
Yes, one end of the cable is plugged into the monitor.. The other end I've checked with the a multimeter with on pin 20, as per the diagram above, and it reads 0 volts.
When I plug in the mDP adapter, and then take another reading, and checking pin 20 on the mDP plug end, the voltage is back up to 3.2 volts.
I'd love it if someone could verify what I'm saying..
Does anyone else have a mini DP adapter like the one above and able to check their voltages?
caveman-jim
New member
I'll double check but it sounds like you're not testing the right pin on the full DP cable. Something has to be passing voltage back.
Quick update, I'm still having issues with one of my displays dropping down to 640x480 after waking from sleep.
Still havn't found a pair of pliers small enough to reach in and pull the pin out. Once I am able to do that I will remove the pin altogether and try again.
I havn't been able to remove the pins yet but it seems as if my "mod" was completely ineffective on this particular cable. What is strange is that I have done the mod on another cable, same brand but longer, and it is perfectly fine.
I'm just wondering if there is some other issue as well due to these cables not being VESA certified. I have switched back to DVI for that one display and have zero issues now (so now have 2 DP and 2 DVI)
I have had almost daily issues with DisplayPort for a long time. Problems waking from sleep and resolution resetting itself.
I tried every suggestion I could find, including using the VESA certified Accell cable. Last month I replaced my NEC PA271w screen with a new Eizo EV2736W. The problem is gone and now everything is working as it should!
So, just to chime into the discussion, that there is a chance the screen is the culprit
I tried every suggestion I could find, including using the VESA certified Accell cable. Last month I replaced my NEC PA271w screen with a new Eizo EV2736W. The problem is gone and now everything is working as it should!
So, just to chime into the discussion, that there is a chance the screen is the culprit
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Looks like the hubs close now Club3D
mini review here
No idea if this product will actually fix this issue outlined here.
Also the product shows a displayport to displayport connection no pic of a mini dp version. If you need a mini to reg displayport connector for your vid card will they also release a 1.2 adaptor or will you be stuck with a 1.1a ?
It will be a pricey solution at best sigh.
mini review here
No idea if this product will actually fix this issue outlined here.
Also the product shows a displayport to displayport connection no pic of a mini dp version. If you need a mini to reg displayport connector for your vid card will they also release a 1.2 adaptor or will you be stuck with a 1.1a ?
It will be a pricey solution at best sigh.
Dr. Zhivago
Well-known member
While it's nice that guru3D took the time to do a mini-review, no word on price and could they have chosen more offensive video material for the demo? That link is NSFW, just so other people reading this will be warned.
caveman-jim
New member
price in the link was 150eur or more.
I'm so glad to finally find people having the same trouble as me.
I recently got a third monitor, so obviously wanted to get Eyefinity working. I had already bought an Apple Mini Displayport to VGA Adapter (which is active, according to the Apple website, which is all I thought I needed).
First time I plugged everything in, stuck at 640x480 on that screen. Did some Googling, someone suggested just unplugging and replugging the adapter, so I did that, and suddenly I could get 1920x1080! However, when I tried to enable Eyefinity, it either just didn't work or set the combined resolution to 1920x480...
I did get it working at one point by playing around with unplugging it, but obviously if I try to swap back to extended displays it breaks again, and I can't easily switch between the 2 as I had hoped to do.
I tried disabling "AMD External Events Utility" as suggested earlier in the thread but that did nothing.
Oh and the one message I've been seeing a LOT from CCC: Link failure in your displayport. :/
If I were to somehow remove pin 20 from the Mini Displayport end of the Apple adapter, would that be likely to fix it?
I recently got a third monitor, so obviously wanted to get Eyefinity working. I had already bought an Apple Mini Displayport to VGA Adapter (which is active, according to the Apple website, which is all I thought I needed).
First time I plugged everything in, stuck at 640x480 on that screen. Did some Googling, someone suggested just unplugging and replugging the adapter, so I did that, and suddenly I could get 1920x1080! However, when I tried to enable Eyefinity, it either just didn't work or set the combined resolution to 1920x480...
I did get it working at one point by playing around with unplugging it, but obviously if I try to swap back to extended displays it breaks again, and I can't easily switch between the 2 as I had hoped to do.
I tried disabling "AMD External Events Utility" as suggested earlier in the thread but that did nothing.
Oh and the one message I've been seeing a LOT from CCC: Link failure in your displayport. :/
If I were to somehow remove pin 20 from the Mini Displayport end of the Apple adapter, would that be likely to fix it?