How to correctly ring the dvi-d port on the video card?

Question

Do it yourself

Good afternoon.
DVI-D Dual link does not work on the AMD Radeon HD 6570 video card. I
plug in a DVI-D Single Link cable - there is no signal. I tried different monitors, different cables (but only single, I don’t have dual cables) - in other computers in dvi-d and in dvi-i I stick all the buzzing with this cable.
I think - it is the connector on the vidyuhi that does not work. Vidyuhu even reflashed. Cho Toko did not try.
There is a multimeter - I don’t know how to use it - tell me where to turn the knob and which holes in the port on the vidyuhi to check. What plug. Red black?
Thank you :)
UPD: All three ports will be occupied for me: VGA monitor, plasma via HDMI and another DVI-D needs to be repaired. And even 4 more monitors are plugged into the integrated video :))

Answer 1

Continuity can find microcontact and breakdown to the ground. Micro-non-contact with modern BGA chips is almost impossible to find without unsoldering the chip. If the conclusions are available: we find the circuit, the tester in “kilooms” or “sound probe”, one end into the connector, the other - to the corresponding output of the microcircuit.
They look for a breakdown to the ground like this: COM to the laptop's ground bus (for example, by the mounting hole, conveniently with a handicraft "crocodile"), "ohms" - to each of the DVI contacts. Earthlings should contact, the rest should not. The mode is the same - "kilooms" or "sound probe".
These are not the only errors; it can burn out inside the video chip and "hang in the air." In this case, with the laptop ON, check if there is any voltage, for example, between Digital Red − and Digital Red +. The mode, of course, is “constant voltage 20 V”. An oscilloscope is, of course, better, but a voltmeter will give some idea of ​​whether there is a current. Hemorrhoids are still like that - poke into a working half-disassembled laptop.
And an external monitor will probably have to be connected to HDMI through an adapter. Not everyone works (checked): there was a case when the DVI cable did not work, but the HDMI cable (through another adapter) worked. On HDMI video, on DVI monitor.