Ken said:What is the basic reason for using digital input/output as opposed to analog signal?
The application is for AutoCad with both 2D and 3D display. Is the main advantage of digital
input for gaming and movies?
Rod, I just googled DVI to try to understand the DVI-I and DVI-D, singleDigital doesnt get degraded by the cable etc.
Nope, anything where you want to maintain image quality.
The degradation happens most at the higher bandwidths,
so at the higher screen resolutions.
Ken said:Rod Speed wrote
Rod, I just googled DVI to try to understand the DVI-I and DVI-D, single and dual.
The present issue is that we have a monitor that, I am told, has some blue lines randomly
appearing when running non-intensive apps but mega-problems when my daughter runs AutoCad.
(She is about 250 miles away). She swapped monitors, cable, etc., and the issue is with her
monitor on the analog circuit (the monitor is just fine on her roommate's computer with either
one's VGA cable.
Her monitor has the VGA adapter and a DVI-I dual link receptacle. Her video card has VGA and
DVI-I receptacles. As I understand it, the DVI-I allows for both VGA and digital signals to be
passed to the monitor. Correct?
Correct.
I do not understand monitors well enough to know
if there are two VGA and one digital circuits.
My thought is this: if we can bypass the VGA circuit by purchasing a DVI cable, then, assuming
there is no digital circuit problem, that would solve her present problem.
If that is true, then I am unclear whether to use a DVI-I or DVI-D cable
and whether to use a single or dual link cable.
So that adds a second question: when does one use a single versus a dual link cable?
Clearly only one monitor connector can be hooked into one DVI-D connector.
This is a bit confusing. I hope I am able to communicate my lack of understanding well enough!!
And had a melt down between the ears |-)
One of the clearer descriptions is
http://en.wikipedia.org/wiki/Dvi
That isnt the sort of problem you normally get
with a cable, its normally a video card problem.
So nothing to do with your original question.
The VGA cable is an analog cable. Presumably you
mean that the problem is with the DVI analog cable.
After what I wrote above with the different experiments do you stillNo there isnt two VGA circuits, just the VGA circuitry is connected to
both the VGA connector and the appropriate pins of the DVI-I connector.
Maybe. We dont actually know whether
the problem is with the digital circuitry tho.
If you want to eliminate the analog signals, you can do that with a DVI-D cable.
That depends on the resolution you are running the monitor at.
For the higher monitor resolutions.
Sure, but it isnt dual in the sense of dual monitors, its dual in the sense
of two digital channels, that can carry twice as much information. A single
digital channel cant go fast enough for the higher monitor resolutions.
Yes, its clear what you are having a problem with.
Ken said:Rod Speed wote
Hmmm.... I realized I forgot one piece of information. The reason
for the video card that we installed a couple of days ago is that the
problem with the lines began when the video was attached to the
on-board VGA controller on her ASUS mb. I think it is an Intel
graphics accelerator. The new card did not solve the problem.
Experiments:
Her monitor/on-board video controller/her cable---> random video lines made worse by AutoCad or
Adobe Illustrator
Her monitor/video card (radeon x800 with 128MB RAM)/cable---> random video lines made worse when
she uses AutoCad/Adobe Illustrator
Other monitor/her video card/her cable. All is well.
Her video card/other cable/her monitor. Same problem.
Other computer and video card/either cable/her monitor Same problem.
Seems like the common factor is the monitor, not the video card,
Yes.
as the video card is just fine running the app with a different monitor and the problem began
before the new video card. No?
Yes.
Sorry I forgot that last bit of info.
No, the VGA cable. She does not have a DVI cable. That is what I am looking to purchase as a
trial to see if the problem is just with the VGA circuit in her monitor.
I think the way to go, then, is with a DVI-D dual link to maximize the digital signal throughput
and eliminate the VGA circuit presumably. Reasonable?
Yes.
I think the native resolution of her monitor is about 1280 x 1024.
After what I wrote above with the different experiments do you still feel it is the video card and
not the monitor?