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I've noticed that there are a lot of requests for dual link DVI capable cards in the video card forums lately. Why do you need dual link DVI? Are you planning on using an LCD that does 2560x1600 or higher anytime soon?
Single link is totally fine up to about 1920x1080, and in analog mode, you can go significantly higher than that. Most video cards manufactured in the last couple of years have at least one dual link DVI port, so finding one shouldn't be a problem, but I still wonder why all of the questions about it lately.
Single link is totally fine up to about 1920x1080, and in analog mode, you can go significantly higher than that. Most video cards manufactured in the last couple of years have at least one dual link DVI port, so finding one shouldn't be a problem, but I still wonder why all of the questions about it lately.
defaultluser
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I think you want a 7800 GS. According to what I've read, it has one dual-link connector just like the rest of the 7800 series.
You might also wait around for this beauty, although when it will be released I have no idea:
http://www.hardforum.com/showthread.php?t=1113192
You might also wait around for this beauty, although when it will be released I have no idea:
http://www.hardforum.com/showthread.php?t=1113192
I'm a little confused, because if you look at the specs listed for evga cards on their site, it says that max res through digital is 1600x1200 (@60hz)...
is that single link? would that res be effectively doubled through the dual-link output? or am i just mistaken completely?
i just bought a sony sdmp-234b and i want to run it at 1920x1200 through DVI...so all 7 series nvidia cards have a dual-link output?
do any 6 series nvidia cards have dual-link outputs? it's just a holdover AGP upgrade until i can go PCI express/dual-core in January...
is that single link? would that res be effectively doubled through the dual-link output? or am i just mistaken completely?
i just bought a sony sdmp-234b and i want to run it at 1920x1200 through DVI...so all 7 series nvidia cards have a dual-link output?
do any 6 series nvidia cards have dual-link outputs? it's just a holdover AGP upgrade until i can go PCI express/dual-core in January...
vizx said:
The TMDS transmitter used by DVI is not design-limited to 1600x1200** over single-link and so most cards that say they can only do 1600x1200 can actually do 1920x1200 with reduced blanking.
In other words dual-link shouldn't be necessary. But more importantly, the Sony SDMP-234b is highly unlikely to have a dual-link input, so a dual-link output on the video card gets you nada.
As long as the TMDS sender in the DVI output is good, single link DVI can (in theory) get to:
- 1600x1200@77Hz -- standard reduced blanking
- 1600x1200@80+Hz -- custom reduced blanking
- 1920x1200@65Hz -- standard rb
- 1920x1200@67+Hz -- custom rb
- 1920x1080@72Hz -- standard rb
- 1920x1080@75+Hz -- custom rb
In practice getting such high resolutions & refresh rates require:
- a good DVI sender (i.e. a good TMDS transmitter)
- a good cable
- a good DVI receiver
- a good DSP in the display, and
- a good internal connection from the DSP to the actual display module.
Many Nvidia 5xxx series GPUs are known to have poor internal TMDS transmitters which may prevent the card doing much more than 1600x1200@60Hz (see here and here). Note however that some cards used external transmitters which were better (see the example of the Asus V9560 Video Suite under the second link).
However, it is actually the last two requirements that are often the killers. For example:
- I have run a Dell 2407fpw at 1920x1200p63.01 over single link DVI from a lowly Radeon 9200 (a Gigabyte GV-R9200-64D which the manual says only does 1600x1200), the reason I can't push it higher is not due to the card, but due to the fact that the Dell uses a Samsung LTM240M2-L02 LCD module that uses a two-channel LVDS interface that is design-limited to a Vsync frequency of 57-63Hz.
- I have helped DTV forum acquaintances get the Pyrod 3711 37" LCD TV up to 1920x1080p72, but no higher (see here).
- in related discussions others in the DTV forum have run an Acer AT3705-MGW 37" LCD TV at 1920x1080p74.4 over single link DVI>>HDMI (see here), BUT to do so they have to trick the Acer by setting the active line to 1912/1919/1921/1928 pixels due to the fact that an active line of 1920 pixels over HDMI is ALWAYS overscanned by the DSP (and DVI>>DVI doesn't work either).
- yet others in the DTV forum have reported that it is impossible to get the BenQ DV3750 (which uses the same LCD module as the Pyrod PW3711) to do 1080p^^, and that is probably due to the DSP BenQ uses.
See here for more commentry and links.
Adrian
** This is indirectly documented in the DVI 1.0 spec, but I have had confimation by e-mail from the technical support guys at Silicon Image (the company that developed TMDS and much of DVI).
^^ BTW the claim of 1080p for the BenQ DV3750 US version via DL-DVI seems questionable, not least because the bloke was doing DL-DVI>>HDMI>>DVI which would have made his process single link. Why? Because DL-HDMI cables are rare as hens' teeth. Although a fair few European websites claim to be selling DL-HDMI products, if you look closely at items such as this Video Dual link HDMI male DVI-D female adapter you'll see that they have 19-pin HDMI Type A connections and DL-HDMI requires a 29 pin Type B connector, so they are actually DL-DVI>>SL-HDMI.