[TechPowerUp article] FreeSync explained in more detail

[BrightCandle]

There are like 6 different manufacturers releasing Gsync monitors this quarter and the next, some of those companies are releasing multiple monitors, so we are looking at quite a lot of available models. The only one you can buy today is the Asus VG248QE.

What I still don't get about Freesync is how often the refresh rate can be changed. Gsync literally makes the GPU the source of the refresh moments but it sounds like Freesync is quite different and can't change the frequency of the monitor continuously. Anyone know what the maximum update rate is exactly? How often can the GPU tell the monitor what refresh it should run at?

 

[BrightCandle]

Those interested in understanding how Freesync works should take a look at the following two documents from Intel and vesa. Both contain details of how dynamic refresh and panel self refresh work, the combination of which is how Freesync does its thing and hopefully you will then be able to see why it requires a prediction of the upcoming frame rate (because the panel refresh rate is set in the secondary data packet after the vblank signal is completed but before the next frame is sent).

https://www.google.co.uk/url?sa=t&r...dqqNxcM2TFF9wNQ&bvm=bv.59026428,d.ZG4&cad=rja

http://www.vesa.org/wp-content/uploads/2011/01/ICCE-Presentation-on-VESA-DisplayPort.pdf

 

[bystander36]

The best case scenario, assuming this is correct, and seems to follow what I suspected earlier, is they can update the refresh after every frame. That still requires prediction, or triple buffering used to look ahead a frame. That would result in a frame worth of latency (17ms-33ms).

 

[Keysplayr]

Do you think NVIDIA paided all the manufactors?
Or is that part also no longer valid?

:sneaky:

just "paid" man.

 

[bystander36]

Another theory on how they might do this would be to use V-sync and triple buffering, with all their rules, and adjust the refresh rate of the monitor every so often to match the FPS of the GPU.

That would give a max latency in the 17-33ms range, but likely less most the time. It won't display things in exactly the same duration as each frame was rendered, but it should be fairly close.

To prevent frames from backing up in triple buffering, which causes an extra frame worth of latency, as DX, triple buffering and V-sync does now when you reach your refresh rate in FPS, they could impose a tiny bit of latency by making the refresh rate slightly slower than the GPU's FPS.

 

[Lonbjerg]

:sneaky:

just "paid" man.

Thx...speaking/writing 4 languages makes some exceptions slip ^^

 

[Keysplayr]

Thx...speaking/writing 4 languages makes some exceptions slip ^^

I'm here to help. 4 languages? Impressive.

 

[Zanovar]

I'm here to help. 4 languages? Impressive.

I bet he cant speak welsh though

 

[Lonbjerg]

I'm here to help. 4 languages? Impressive.

Only 5.2 millions speak danish...it's a necessity

I bet he cant speak welsh though

I don't even think welsh people can speak proper welsh

 

[Zanovar]

Only 5.2 millions speak danish...it's a necessity



I don't even think welsh people can speak proper welsh

North wales mostly,i can speak it kind ofbadly

 

[antihelten]

Those interested in understanding how Freesync works should take a look at the following two documents from Intel and vesa. Both contain details of how dynamic refresh and panel self refresh work, the combination of which is how Freesync does its thing and hopefully you will then be able to see why it requires a prediction of the upcoming frame rate (because the panel refresh rate is set in the secondary data packet after the vblank signal is completed but before the next frame is sent).

https://www.google.co.uk/url?sa=t&r...dqqNxcM2TFF9wNQ&bvm=bv.59026428,d.ZG4&cad=rja

http://www.vesa.org/wp-content/uploads/2011/01/ICCE-Presentation-on-VESA-DisplayPort.pdf

Just curious, but are you sure freesync uses PSR?

As far as I know AMD hasn't stated anything of the sorts (although that doesn't make it impossible of course), but they have stated that they have been capable of doing freesync with their last 3 generations of GPUs, which would more or less rule out using eDP 1.3 (which was the first time the eDP standard featured PSR). I would have thought that using something like seamless refresh rate switching, which has been a part of eDP since version 1.0, would make more sence.

 

[3DVagabond]

It won't be 300.00 for long. When more monitor companies release their G-Sync ready monitors, the prices, LIKE ANYTHING ELSE, will come down. Jeez, why don't you just switch over already. It would save you a lot of very difficult and hard to pass off arguing.

Maybe it won't be $300 for long, but it is was it is. We're supposed to show unequivocally anything to do with AMD, but it's alright to used deductive reasoning with nVidia products. Besides, with nVidia the only time they show a willingness to reduce prices is when there's competition that dictates it. Until that happens they keep their pricing high. Why should we think Gsync would be any different? As long as they have the market cornered on it they always keep pricing high. That's just the way they operate.

 

[bystander36]

Maybe it won't be $300 for long, but it is was it is. We're supposed to show unequivocally anything to do with AMD, but it's alright to used deductive reasoning with nVidia products. Besides, with nVidia the only time they show a willingness to reduce prices is when there's competition that dictates it. Until that happens they keep their pricing high. Why should we think Gsync would be any different? As long as they have the market cornered on it they always keep pricing high. That's just the way they operate.

There are already vg248qe's with the Gsync DIY kit installed at $200 over their normal price. I'm not sure these 1440p G-sync monitors are that high due to G-sync, but also due to 120hz and Lightboost like G-sync feature, not to mention those 1440p monitors are completely new products.

We'll have to wait and see, but there is a lot of new stuff on these monitors, and they are pricey. Let's just hope it'll come down soon.

 

[BrightCandle]

Just curious, but are you sure freesync uses PSR?

As far as I know AMD hasn't stated anything of the sorts (although that doesn't make it impossible of course), but they have stated that they have been capable of doing freesync with their last 3 generations of GPUs, which would more or less rule out using eDP 1.3 (which was the first time the eDP standard featured PSR). I would have thought that using something like seamless refresh rate switching, which has been a part of eDP since version 1.0, would make more sence.

Without confirmation from AMD I can't be sure, but its important to realise that currently eDP monitors don't normally support going below 40hz (for the same reason gsync has a minimum of 30hz presumably). So I suspect PSR or maybe just repeated frames by the GPU are used to get the intermediate images displayed. I found out about PSR along the way of looking up the dynamic refresh and its very much a related technology, according to Intel, so thought I would mention it since they did in their presentation.

 

[3DVagabond]

There are already vg248qe's with the Gsync DIY kit installed at $200 over their normal price. I'm not sure these 1440p G-sync monitors are that high due to G-sync, but also due to 120hz and Lightboost like G-sync feature, not to mention those 1440p monitors are completely new products.

We'll have to wait and see, but there is a lot of new stuff on these monitors, and they are pricey. Let's just hope it'll come down soon.

Yeah, I see where you are going to be able to buy them for $500 or have one installed on an existing monitor for $300, or the kit alone and do it yourself for $200. I assume Asus isn't going to be willing to warranty these modded monitors though?

 

[Lonbjerg]

Maybe it won't be $300 for long, but it is was it is. We're supposed to show unequivocally anything to do with AMD, but it's alright to used deductive reasoning with nVidia products. Besides, with nVidia the only time they show a willingness to reduce prices is when there's competition that dictates it. Until that happens they keep their pricing high. Why should we think Gsync would be any different? As long as they have the market cornered on it they always keep pricing high. That's just the way they operate.

Is there a reason you won't answer the simple question if the are differences between AMDs' PR and NVIDIA's products?
You ran away from the TrueAudio debate too...is that the M.O....run away when facts disagree with you? :biggrin:

 

[3DVagabond]

Is there a reason you won't answer the simple question if the are differences between AMDs' PR and NVIDIA's products?
You ran away from the TrueAudio debate too...is that the M.O....run away when facts disagree with you? :biggrin:

Not running, still here. When you ask a legitimate question I'll be happy to discuss it with you. You just keep making the same point that these things aren't available yet. We know that. It's not some great revelation. GSync isn't available yet either. We know it will be soon though, and that's good enough. Good enough when it's nVidia, that is. When it's AMD you call it empty PR. That's just a stupid argument that isn't even worth replying to. So keep making your empty points since it seems to be the limit of your ability to discuss anything.

 

[sontin]

G-Sync is available. You can buy the DIY kit or a modified monitor now.
There are people who won the DIY kit from various sites.

On the other hand FreeSync is vaporware.

 

[Gloomy]

Are they selling the 2560x1440 kit? I may be able to put it on my monitor if so. Would be an interesting experiment. It just fits where the scaler goes right?

 

[Erenhardt]

On the other hand FreeSync is vaporware.

Not quite... If I remember correctly they showed freesync on existing products - the same nv did 2 months ago with gsync, but I cant remember anyone calling it then vaporware.

 

[3DVagabond]

G-Sync is available. You can buy the DIY kit or a modified monitor now.
There are people who won the DIY kit from various sites.

On the other hand FreeSync is vaporware.

Is it? That's good. All I saw was pre order. Which is fine. It's not like their was any doubt that it was coming. I'm sure FreeSync, or whatever it ends up being called, will happen too.

 

[sontin]

Not quite... If I remember correctly they showed freesync on existing products - the same nv did 2 months ago with gsync, but I cant remember anyone calling it then vaporware.

They showed nothing.
I saw a static video with a windmill and V-Sync. That is not a sign of existence.

nVidia demonstrated everything and let people use it.

 

[ShintaiDK]

Not to mention all the OEMs that public support g-sync. Not a single OEM with a statement about "free"sync.

"Free"sync was nothing more than a desperate PR stunt to throw some dirt.

 

[antihelten]

G-Sync is available. You can buy the DIY kit or a modified monitor now.
There are people who won the DIY kit from various sites.

On the other hand FreeSync is vaporware.

Actually I don't think you can get G-Sync right now as all the kits and monitors are sold out (falcon northwest and maingear might still have some, but there you have to buy an entire system to get one), there should be another batch in a week or so however.

Also to put it mildly it's a bit hyperbolic to call something that was announced 5 days and not as an actual product, vaporware.

Not to mention all the OEMs that public support g-sync. Not a single OEM with a statement about "free"sync.

"Free"sync was nothing more than a desperate PR stunt to throw some dirt.

The question isn't really how many OEMs make a statement of supporting freesync, the question is how many of them make a statement of (fully) supporting DisplayPort 1.3.

 

[ShintaiDK]

Also to put it mildly it's a bit hyperbolic to call something that was announced 5 days and not as an actual product, vaporware.

When AMD says they are not ready to productize it or any plan to go to market. Then its vapourware.

AMD isn’t ready to productize this nor does it have a public go to market strategy

http://www.anandtech.com/show/7641/amd-demonstrates-freesync-free-gsync-alternative-at-ces-2014