Why does GSync not work with an HDMI cable?

[Arya]

I'm curious why G-Sync only works on Displayport and not HDMI. What are the differences between the two, and why does the type of cable I use effect a seemingly unrelated onboard system like Gsync?

[SundownKid]

Apparently HDMI only supports up to 1080p 60 fps or something, making Gsync kind of pointless.

[Arya]

Messaggio originale di SundownKid:

Apparently HDMI only supports up to 1080p 60 fps or something, making Gsync kind of pointless.

At a glance they look almost identical - does the Displayport support more data traffic or something?

I'm not doubting the effect, but I very curious as to the cause. I accidentally flattened my Displayport cable last week and had to get by with an HDMI, which as you said locked my monitor to 59.9 Hz and disabled Gsync. It didn't lock it to 1080p, although I was running at 1080p because my 970 struggles to handle 1440p.

[SundownKid]

Yes, Displayport has more bandwidth and a more modern way of transmitting data. It's simply better than HDMI at most stuff.

[Arya]

Messaggio originale di SundownKid:

Yes, Displayport has more bandwidth and a more modern way of transmitting data. It's simply better than HDMI at most stuff.

Thanks, I thought so.

[Bad 💀 Motha]

yes DisplayPort is the way to go for anything above 1080p/60Hz

[Washell]

Good summary: https://www.reddit.com/r/buildapc/comments/4p0q7a/lets_talk_about_vsync_freesync_gsync_adaptivesync/

[bit2shift]

Messaggio originale di SundownKid:

Apparently HDMI only supports up to 1080p 60 fps or something, making Gsync kind of pointless.

Incorrect.
HDMI 1.4 supports 1920×1080 at 120 Hz. It can even handle 2560×1440 at 75Hz.

[Azza ☠]

DisplayPort originally had much higher bandwidth support than DVI or HDMI. The G-SYNC microchip therefore was designed to run via it.

Later on, HDMI caught up, etc... but it still uses DisplayPort only, due to the hardware is intergrated there already. It would cost more to change or have them all support it.

[DonJuanDoja]

HDMI 2.1 was just released in Nov and it supports 4k-10k...

Of course each device would have to support it... etc.

Wikipedia article on HDMI explains it pretty well.

[Dr.Shadowds 🐉]

Messaggio originale di Azza ☠:

DisplayPort originally had much higher bandwidth support than DVI or HDMI. The G-SYNC microchip therefore was designed to run via it.

Later on, HDMI caught up, etc... but it still uses DisplayPort only, due to the hardware is intergrated there already. It would cost more to change or have them all support it.

^This.

Messaggio originale di bit2shift:

Messaggio originale di SundownKid:

Apparently HDMI only supports up to 1080p 60 fps or something, making Gsync kind of pointless.

Incorrect.
HDMI 1.4 supports 1920×1080 at 120 Hz. It can even handle 2560×1440 at 75Hz.

You have to look at the product manual to ensure the monitor support 120+Hz over HDMI, it is not enough just to have a laptop or graphics card with an HDMI 1.3 or 1.4 port. The display must support 120+Hz over HDMI, and the HDMI version alone will not tell you if the monitor supports it. Some monitors are limited to 60 Hz over HDMI even if they have HDMI 1.3 or HDMI 1.4 inputs. This is a limitation of those monitors, not a limitation of the HDMI standard, this is pretty much the only reason why I never really like HDMI because of the manufacturers decisions.

[Bad 💀 Motha]

Yea look at the specs page on the official branded site for the model in question.
It will state requirements of sorts; like the need to maybe use DVI-D or DP in order to use G-Sync. Its just how it is. Why anyone would use anything besides DP is beyond me.

[Dr.Shadowds 🐉]

Messaggio originale di Bad_Motha:

Yea look at the specs page on the official branded site for the model in question.
It will state requirements of sorts; like the need to maybe use DVI-D or DP in order to use G-Sync. Its just how it is. Why anyone would use anything besides DP is beyond me.

It's beyond me as well, normally they give you the cables that are needed to make full use of the monitor from the start anyways, which are normally DVI-D DL, or DP, as HDMI wouldn't even be good option when it comes to high refresh rate monitors, or GSync. Also the fact remains if the person didn't get the proper cables with the monitor, you either contact the company to send you the cable that was needed which can be free, but the wait time will be fun, or you could go out to buy the proper cable, or order it online, which is like $5 - $15.

[John Doe]

HDMI 2.0 has supported 4k at 60 HZ for some years now. While Displayport is clearly better than it for most usages, both Displayport and HDMI recently got new standards supporting up to 8k.

[Dr.Shadowds 🐉]

Messaggio originale di John Doe:

HDMI 2.0 has supported 4k at 60 HZ for some years now. While Displayport is clearly better than it for most usages, both Displayport and HDMI recently got new standards supporting up to 8k.

HDMI 2.0 - 2013 = 4k 60hz
4 years gap time of release.
DP 1.2 - 2009 = 4k 75hz

HDMI 2.1 - 2018 = 8k 30hz without DSC.
4 / 2 Years gap time of release.
DP 1.3 / 1.4 - 2014 / 2016 = 8 30hz without DSC.

DSC = Display Stream Compression.

[Bad 💀 Motha]

All these specs are meaningless though; you're not doing G-Sync via HDMI on a majority of all Displays that support G-Sync, period. That's going by what is out right now and what a GPU such as GTX 9xx or 10xx can support.