Widescreen Gaming Forum

So I've posted in other threads but haven't gotten any replies. And I've read where you can use one dual output video card to drive a digital triple head 2 go (dth2go), and use the remaining output on the video card to drive a 4th monitor.

I have a dual dvi output card(gtx295) and it is currently driving a DTH2GO with three 24" monitors. I recently aquired a 17" 4:3 dell flat panel and I'm trying to use it as a secondary(read: quadrary) monitor while I'm gaming on the 3-span.

Here's the thing, with the new monitor plugged into the second output on the video card, I can't get it to enable and come on to display anything. Example, In windows pane, I can click the tick box " extend my windows desktop onto this monitor" and when I click apply, they all go black for a sec, then the triple span come back on, and the tick box is unchecked again.

Ive tried the windows display panel and the nVidia one but no luck. Is this even possible? or do I need a secondary video card?

thanks,
Cj

In my setup, I drive three monitors with 1 dth2go + 3 separate outputs to the three mons, so I can use th2go or softth. With all enabled, windows sees four screns, but there are only three physical ones.

Just now, I have a 285gtx+8800u, but when I had 8800u+8800gts320, I couldn´t do the same thing. I could have 2x2560x1600, but not 2560x1600 + 5040x1050 (or even 2560x1600 + 3840x1024 or similar, so is not a bandwidth problem, but an aspect ratio one, maybe driver related).


Saludos

so... are you implying that I do need a secondary graphics card? or are you saying it is a driver related conflict? or are you saying that I need to implement some sort of soft th2go? I'm confused :)

I don´t know exactly whats the problem (maybe driver related), but in my case, it solved when changed from 8800u to 285gtx as main card.

For ex: 8800u could not work with 2560x1600 + 3840x1024 (althought it can do 25x16 25x16), even if 3840x1024 has less pixels, but 285gtx does.


In your case, why dont you try the 295gtx third output (hdmi)? (with an adapter if neccessary).

ya, I've tried the HDMI to no avail. I'm beginning to think that since the DTH2GO uses a dual-link dvi cable, it is using both links of the gtx295, and therefore there are no more links left to drive a seperate monitor. In your situation, you are running two, dual-link graphics cards, which effectively gives you 4 links, and the ability to run more monitors.

Doesn't anyone here have experience with this setup? Single graphics card with triple head 2 go and one extra monitor?

ya, I've tried the HDMI to no avail. I'm beginning to think that since the DTH2GO uses a dual-link dvi cable, it is using both links of the gtx295, and therefore there are no more links left to drive a seperate monitor. In your situation, you are running two, dual-link graphics cards, which effectively gives you 4 links, and the ability to run more monitors.

But the 295gtx has 2x dual link, not a dual link to spare for two outputs. Even my old 8800gts320MB can manage 2x2560x1600, wich needs obviously 2xdual link output, althought cannot do 2560x1600 + 3840x1024 (8800u also cannot do), and this is with the same drivers than my 285gtx, so I think now is probably an electronics issue from the card board.


Anyway, It seems you´ll need another card, wich is a shame having a three outputs card.

That's kinda odd. I've tried one single GPU driving 4 monitors (3 connected to TH2Go and 1 connected to the 2nd DVI) and it worked. You don't need a second video card.

I have an ATI crosffire set up btw. Maybe Nvidia is different?

well, after some fiddling, I figured it out. Since my gtx295 is a two board sli card in one slot, I have an option in my nVidia control panel called "enable multi-gpu mode" and If I disable this mode, it runs all 4 monitors fine... but I'm assuming it is only using one gpu to run the triple span, which is ok for what I need it for, and I can just re-enable it for more intensive games.

all is well!

Thanks
cj

well, after some fiddling, I figured it out. Since my gtx295 is a two board sli card in one slot, I have an option in my nVidia control panel called "enable multi-gpu mode" and If I disable this mode, it runs all 4 monitors fine... but I'm assuming it is only using one gpu to run the triple span, which is ok for what I need it for, and I can just re-enable it for more intensive games.

all is well!

Thanks
cj

good job finding the culprit yourself!

it's exactly as you said it... SLI can support only 1 output
though I wonder how is treated the workload with 2 outputs on a single SLI card
Optimally one GPU should be used for each output