Question / Help Datapath VisionSC-DP2 & GSYNC?

[unph4zed]

I've been waiting for a Displayport 1.2 capture card for quite sometime. My previous capture card was the Vision DVI-DL.

The VisionSC-DP2 has caught my attention and is very close in price to the DVI-DL. I'm assuming it will have to go through an active splitter just like the DVI-DL. I know you can daisy chain with DP but my exposure to it is very limited. With that said, I also don't know if the GSYNC 'handshake' will still take place through the splitter. Does anyone have the know-how to answer this?

http://www.datapath.us/visionsc-DP2-datapath.php

 

[EDGAR_SEC]

Thanks for the heads-up on the card; I just placed my order.

From what I've read on GSYNC in the past, I'm guessing the splitter itself would need its own gsync chip, right? I just don't see how it would be able to pass through.

On a somewhat question: have you found any active displayport 1.2 splitters? I've been searching for the longest time for one. Knowing how much Gefen charged me for the DVI splitter I needed for my VisionDVI-DL, I'm predicting a Displayport1.2 version might cost us $800. Ugh.

Would gsyncing a 60hz 4K monitor even been desirable since wouldn't it just feel like VSYNC-ish input lag? I was mainly interested in this card so I could play locally at 4K and use a 1:2 downscale.

 

[unph4zed]

I don't know enough of the technical aspects behind gsync to give a decent answer but from what I've read it has vastly improved. http://www.blurbusters.com/gsync/preview2/ I don't think you would feel input lag the same way vsync feels like utter garbage. As far as the chip, I hope it will actually pass through the splitter and receive the handshake through the primary output. I can't imagine why the splitter would interfere unless it introduced cross-talk between the 2 outputs.

The only splitters I've found have been from google searching 'Displayport 1.2 powered splitter' which returns a bunch of unreviewed crap for about $50. Nothing I've found looks like it is decent quality. Gefen only makes a 1.1 splitter right now which would probably work if you stayed under the spec. Might work for me because all I care about is gsync and not 4k.

Edit: I also wonder if clone mode hurts SLI performance the same using DP as it does with DVI. I would assume so but hmmm...

 

[EDGAR_SEC]

As far as the chip, I hope it will actually pass through the splitter and receive the handshake through the primary output. I can't imagine why the splitter would interfere unless it introduced cross-talk between the 2 outputs.

From my understanding on how Gsync works, the display device needs a Gsync chip in order for the GPU to control its variable refresh rate. When running it through a splitter, I'd imagine it needs its own receiving chip, plus two "output chips" to then sync up with the monitor and the capture card. The splitter would then probably need some extra ICs to have the input and the outputs "talk" to each other.

I also don't think any capture card out there would ever support gsync for economic (one chip adds $150 to a monitor right now) and practical reasons (the target market for Datapath isn't really BF streamers like us).

The only splitters I've found have been from google searching 'Displayport 1.2 powered splitter' which returns a bunch of unreviewed crap for about $50. Nothing I've found looks like it is decent quality. Gefen only makes a 1.1 splitter right now which would probably work if you stayed under the spec. Might work for me because all I care about is gsync and not 4k.

Edit: I also wonder if clone mode hurts SLI performance the same using DP as it does with DVI. I would assume so but hmmm...

I'd guess the same SLI cloned issues would exist since displayport seems to be an extremely similar re-pinned DVI. The interesting thing is that DVI technically doesn't have a pixel clock limit as long as the cabling, source, and display all have the necessary build quality to handle what's thrown at it.