Beware the DMS59 connector on a video card
A while ago one of our team mentioned noticeable differences between his two monitors. One was using DVI via a display port to DVI adapter and the other was connected with a VGA cable. Because I know hardware is cheap and people are expensive I purchased some dual DVI video cards for our workstations. These were purchased from the workstation manufacturer and are the half height cards needed for our small form factor systems. They came in today and one of the team started installing it along with a dual DVI KVM. The cards are ATI Radeon 6350 DMS59 cards that have a single DMS-59 connector with an adapter that splits the DMS-59 into two DVI connections. For some reason he couldn’t even see the BIOS boot screen. Hearing the problems one other person on the team and I gave suggestions as we went about our work. Things like reconnecting the display port and going into the BIOS to disable the on-board video. About 2 hours into this I decided to help out and started methodically going through troubleshooting steps.
The first thing was to eliminate the KVM; no help. Then I tried connecting the monitor to the different plugs on the adapter cable which were labeled 1 and 2; still nothing. Then I removed the adapter cable (DMS-59 to dual DVI) to check and see if there were any bent pins; nope. I looked at the adapter to make sure I put it on correctly and then go to connect the monitor cable to plug 1 again. This is when I noticed something strange. When I was previously connecting the monitor cable to plugs 1 and 2, I could easily see the 1 and 2 markings on the plugs; they were facing up. Now I have to turn the plug over to see the 1 and 2 markings. I remove the adapter, flip it over, and now I can see the 1 and 2 markings just like I did before. I push the adapter onto the DMS-59 connector and it slides on without a problem! I flip it over (the way it should be) and it slides on just fine. I connect the monitor, turn on the computer and see the BIOS boot screen. So even though the DMS-59 connector is D shaped the adapter is so poorly made that it can be put on either way. The other team member opens his and tries putting the connector on the wrong way; slides right on. I open the third box and sure enough, the adapter can go on both ways.
Besides the adapter being so poorly made that it can be attached upside down there is another problem. A DMS-59 connector is supposed to have one pin blocked. But the connector on the video card didn’t meaning it wasn’t a DMS-59, but instead a low-force helix connector. So the bottom line is to be careful when using these types of adapters on these type of connectors. The adapter may very well have the ability to be connected upside down and troubleshooting the problem may not be as simple as it may seem.