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Old Jan 27, 2013, 04:45 PM  
Join Date: Aug 2012
Location: United States FL
Posts: 21
Craz is still being judged by the masses


Originally Posted by caveman-jim View Post
I had better luck with 13.1 and 13.2 and eyefinity after I swapped out my display port dongles, apparently 12.11 wasn't as sensitive? somthing changed anyway... very odd. looking at buying new cables now.
Check your displayport cables when I was troubleshooting the x79 system hang awhile back I found my cables were not compliant with VESA standards. I used to get displayport link failure messages all the time. Here is some info from my post i made on another website:

If you read the VESA Displayport standard it states.
Here on page 147

3.2.2 DP_PWR Wire

A standard DisplayPort cable must have no wire for the DP_PWR pin.
Only captive cables supplied with cable powered Branch Devices or cables permanently attached to Sink
Devices are permitted to have the wire for DP_PWR. These captive/attached cables must have a standard
DisplayPort plug connector (as specified in Section 4.2.1) on one end only. The other end must either be
permanently attached or have a custom connector.

If you look at the pin out for a DP cable.

Pin out

External connector (source-side) on PCB
Pin 1 ML_Lane 0 (p) Lane 0 (positive)
Pin 2 GND Ground
Pin 3 ML_Lane 0 (n) Lane 0 (negative)
Pin 4 ML_Lane 1 (p) Lane 1 (positive)
Pin 5 GND Ground
Pin 6 ML_Lane 1 (n) Lane 1 (negative)
Pin 7 ML_Lane 2 (p) Lane 2 (positive)
Pin 8 GND Ground
Pin 9 ML_Lane 2 (n) Lane 2 (negative)
Pin 10 ML_Lane 3 (p) Lane 3 (positive)
Pin 11 GND Ground
Pin 12 ML_Lane 3 (n) Lane 3 (negative)
Pin 13 CONFIG1 connected to Ground1)
Pin 14 CONFIG2 connected to Ground1)
Pin 15 AUX CH (p) Auxiliary Channel (positive)
Pin 16 GND Ground
Pin 17 AUX CH (n) Auxiliary Channel (negative)
Pin 18 Hot Plug Hot Plug Detect
Pin 19 Return Return for Power
Pin 20 DP_PWR Power for connector (3.3 V 500 mA)

On a standard Displayport cable being used to hook up monitor to video card.
Pin 20 DP_PWR Power should not be connected. It is back feeding 3.3v back into the video card causing all kinds of issues. A lot of company are pushing out products that are not following the correct VESA Displayport Standards.

I tested this by removing my video card and connecting Displayport cables. These are Monster Digital Life cable.

Measured here from negative lead on meter to screw on back of card.

And Reading 3.3v on video card. (MSI 7970 reference card)

The cables I found to be compliant are Belkin Displayport Male to Displayport Male. I did away with using the Mini-DP to DP cables and am using the Mini-DP to DP female dongle that was included with my MSI reference 7970's.

Here is a link to the compliant cables.

I tested monster displayport cables and some cheap startech cables. Both were non compliant pin 20 was connected back feeding 3.3v. Belkin is the brand of cable I am using now. I havent had a displaylink failure since switching to the belkin compliant cables.

Anyways, I hope someone finds this info usefull..

Last edited by Craz : Jan 27, 2013 at 07:55 PM.
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