Dual-DVI: Noise on 2nd LCD Screen *VIDEO*

[Jenova314]

I recently bought this Radeon 9600 Dual-DVI card from newegg, hoping to finally run Dual-DVI on my two Planar 19" monitors. I have the Planar PL1910M, and the PX191, used as the primary, and secondary displays, respectively.

However, the secondary DVI-out of the HIS card keeps producing horizontal noise, as seen in this video (right-click, save as, and rename to zip). Important note about clip: the screen has vertical pivot mode enabled, thus the horizontal lines are seen as vertical in the clip.

Here's what I've done to troubleshoot so far:

1) RMA the screen (previous was PV174, Planar took the liberty to upgrade to PX191 for my replacement).
2) Switch DVI output between my two displays.
3) Bought new Dual-link DVI-D cables
4) RMA'd card from newegg.
5) Newest drivers from ATI (doubt this is an issue)
6) Different frequencies (60, 70, and 75Hz)
7) Alternate DVI mode and Reduce Frequency in the options menu

Nothing seems to work, I've tried different DVI-cables, and different displays. It would seem that the secondary DVI output of this HIS card is inherently flawed (happens on the PL1910M too if I switch the cables around). I've emailed HIS (the manufacturer, a HK company) asking for detailed information about the TMDS transmitter(s) used on the card, but received no reply (3 weeks now).

Has anybody had similar issues with this card?? I'm hoping there is some stupid/simple setting/option that I'm missing.

Edit: The problem temporarily goes away if I change the frequency of the display from "display properties," either 60, 70, or 75Hz.

 

[Viper96720]

Tried alternate dvi mode and/or reduce frequency in the options menu of advance video settings

 

[Jenova314]

Originally posted by: Viper96720
Tried alternate dvi mode and/or reduce frequency in the options menu of advance video settings

Tried before, to no avail.

 

[Jenova314]

bump

 

[ponyo]

Looks like you've tried pretty much everything already. I wouldn't even have gone as far as you have. It looks like it's just crappy product from HIS and doesn't work as advertised. I would just return it to Newegg and just get an another card from a different company. Sorry I think I recommended this card to you. Didn't know it didn't work as advertised.

I don't remember if you said if you gamed or not but if you don't, Matrox P650 has Dual DVI and is pretty much guaranteed to work great. You could have Newegg swap it for this and pay the small difference.
Matrox P650 Dual DVI

If you game then this XFX 6600GT AGP has Dual DVi but it's expensive.
xfx 6600gt dual dvi

Dual DVI is important feature to me as well as I'll likely pick up Dell 2005FPW in the future. My BFG 6800 Ultra OC is Dual DVI and the first card I've owned that is so.

Good luck and I hope you get this resolved. Sorry I couldn't be more of a help.

 

[Jenova314]

bump

 

[HappyNic]

did you try setting different resolutions on either LCD? like 1 is at 1280x1024 and the other at 1024x768?

 

[Jenova314]

Originally posted by: HappyNic
did you try setting different resolutions on either LCD? like 1 is at 1280x1024 and the other at 1024x768?

yes i've tried, not that i should have to do that, at all, since the LCDs' native resolutions are both 1280x1024. anyways, the noise is still there.

 

[Karri]

I'm afraid this isn't any help but I had a similar problem to yours. Only one of my XFX GeForce 6800's DVI outputs works on high resolutions (1280 and up). At high resolutions you can see horizontal noise which is especially pronounced on black background. I couldn't download your video but I guess it's quite similar problem to yours. After some research I came to the conclusion that DVI connection requires very high quality components to work at high frequencies, components which are rarely seen in consumer grade display cards. For example, some tests at Tom's Hardware proved that the DVI signal quality on most cards can barely support 1600x1200 resolution at all.

 

[Jenova314]

Originally posted by: Karri
I'm afraid this isn't any help but I had a similar problem to yours. Only one of my XFX GeForce 6800's DVI outputs works on high resolutions (1280 and up). At high resolutions you can see horizontal noise which is especially pronounced on black background. I couldn't download your video but I guess it's quite similar problem to yours. After some research I came to the conclusion that DVI connection requires very high quality components to work at high frequencies, components which are rarely seen in consumer grade display cards. For example, some tests at Tom's Hardware proved that the DVI signal quality on most cards can barely support 1600x1200 resolution at all.

Edit: video refuses to be downloaded

 

[Karri]

Anyway, I believe this page explains the problems with secondary DVI outputs:
http://graphics.tomshardware.c...tft_connection-08.html
Main DVI output uses GPU's built-in DVI chip but external DVI chip is needed for the secondary DVI output. This external DVI chip can be much lower quality than the built-in and has nothing to do with GPU manufacturer. I guess the built-in chip is usually used on the DVI port further away from the AGP connectors as shown on the pictures. My broken DVI output is the lower one.

Ok, I just saw your video and its much more visible problem than mine. The same theory of low quality secondary DVI outputs might still very well apply.

 

[Jenova314]

Originally posted by: Karri
Anyway, I believe this page explains the problems with secondary DVI outputs:
http://graphics.tomshardware.c...tft_connection-08.html
Main DVI output uses GPU's built-in DVI chip but external DVI chip is needed for the secondary DVI output. This external DVI chip can be much lower quality than the built-in and has nothing to do with GPU manufacturer. I guess the built-in chip is usually used on the DVI port further away from the AGP connectors as shown on the pictures. My broken DVI output is the lower one.

Ok, I just saw your video and its much more visible problem than mine. The same theory of low quality secondary DVI outputs might still very well apply.

yea that's actually the article i read before making this thread. it would seem there needs to be a better way for us to know what TMDS chips are used for the secondary ports.

 

[Jenova314]

looks like i'm not the only person with this problem.

i did some googling, and there's a thread on stanchina.net regarding this exact same card here

 

[Jenova314]

last bump