AMD demonstrates Freesync, G-sync equivalent?

Since PS4 has [equivalent of] GCN 1.1 and big TV division, I would very much want them to think about looking into this tech. They promote PS4 as "gamer-first" console, and adaptive refresh rate would be great addition to their marketing efforts.

 

I can't begin to imagine the logistical headache of trying to get TV manufacturers onboard and to follow specs; HDCP has been a constant PITA since its introduction, and indeed even HDMI as such has had interoperability issues between various pieces of equipment. Layering another scheme on top of that is like begging for trouble.

Also, I can imagine the interest is limited, seeing as the market share would start from zero: you'd need to buy a new TV - and possibly a new PS4 as well to make it work.

 

Firmware + driver:

http://www.tftcentral.co.uk/news_archive/33.htm#benq_xl2730z_firmware

 

So, a simple firmware fix on the Benq monitor to get anti-ghosting with Freesync.

Also looks like the Nixeus NX-VUE24 monitor will has anti-ghosting (overdrive) working with Freesync as well...

http://www.overclock.net/t/1546934/various-amd-freesync-reviews/1660#post_23863846

From that post it seems it's just a tuning issue to get the overdrive timings correct when Freesync mode is on. The rush to be one of the first monitors out with Freesync likely meant that most (if not all) monitors released initially didn't have time to do tuning to have overdrive work with Freesync.

As well, now that Gsync officially doesn't need special hardware to work (their laptop Gsync does it the same way as AMD's Freesync with tuning of overdrive timings in firmware to get it to work), hopefully Nvidia will support Adaptive sync sooner rather than later. Then again that would cut out their high margin G-sync module revenue, so I doubt it will happen. /sigh.

Regards,
SB

 

I believe there would still be differences in implementation of the initial tuning of each LCD panel:

 

I wonder how FreeSync over HDMI works. Since, unlike DP, the pixel clock is directly derived from the TMDS clock. I guess though could just playing tricks (so the pixel clock is corresponding to the max pixel clock, but effectively the scaler uses its own independent clock, which it might do anyway). I guess in the end it doesn't matter all that much if the signel came from HDMI or DP if you do that.

 

I dont know, but maybe we should look how work the Nvidia driver who have been out today who introduct too, HDMI support . ( we can applauze the hazard )

 

Since I play games on a large HDTV having HDMI TVs with VRR support would definitely be a feature that would sway me. One can hope.

 

http://www.tftcentral.co.uk/reviews/acer_xr341ck.htm

Acer XR341CK is a curved 3440x1440 IPS screen with 30-75Hz Freesync support. The panel overdrive has been "optimised" for Freesync usage, with 0 overshoot. Pixel response times are slightly slower when Freesync is enabled.

There appears to be a bug when running this monitor with NVidia, with frames being dropped. Pretty weird.

 

The funny thing is this monitor has issues even running AMD cards w/o Freesync support, or whether you choose to use HDMI instead of DP. Releasing broken products seems to be the trend for Freesync monitors ... is it worth the price of $1000+?

 

I suggest you apply some reading comprehension.

 

I wonder when monitors will start arriving with USB ports for in-situ firmware updates. By the looks of it, this should have happened already, considering all the chaos several manufacturers have had with certain recent models.

 

Freesync only works with DisplayPort, so I don't even get why they even tried it with HDMI. Didn't they even read the manual, or anything about the tech?

 

The monitor should still work on a fixed refresh rate via HDMI right? I'd guess a substantial number of purchasers of this monitor will never use freesync on it for one reason or another.

 

Everything works fine.
The only thing that doesn't work is overdrive (IIRC refresh rate over 60Hz?) using nVidia cards or AMD using HDMI.
The AMD + HDMI is obvious because AMD cards only support HDMI 1.4 and its bandwidth can't handle more than 2K @ 60Hz, and this monitor's resolution is sort of "2.5K".

 

Dummy question incoming: WTF is overdrive?

 

Overdrive is a way to reduce the pixel response time by electrically driving the pixels using a voltage peak that is significantly higher (or lower) than the actual target voltage for a fraction of a millisecond.

Simplified, imagine you want to go from black to mid-grey. Instead of using the target voltage for mid-grey and waiting until the pixel changes to that colour, you set the voltage for white, wait until the pixel is about to reach mid-grey, then drop the voltage to that level. The higher voltage causes the pixel to change more rapidly. The problem is that if you don't get the timing exactly right, the pixel will overshoot and you'll get light grey for a short moment.

 

Oh cool that sounds like a great idea.

 

On paper, but it isn't perfect and you can end up with overdrive inducing ghosting on its own by overshooting the value that was requested. Better monitor manufacturer's run into this less often than lesser known manufacturers but it usually still exists to some extent with them. That said, some find that minor ghosting better looking than non-overdrive ghosting.

Regards,
SB

 

I was tend to believe that overdrive in some case can create reverse ghosting ( the "ghost" is before the image not after it ), and effectively this is not allways visible and to a certain extend, less problematic that the known ghosting effect.