How G-Sync and FreeSync differ right deep down inside

[Frag_Maniac]

So what? It doesn't matter. When you go below 40 Hz you start getting visual artifacts. Does it work below 40 Hz? Yep it does. Will it look good? Nope. But AMD won't tell you that because you won't support their product like you are now.

Until we actually SEE tests of Freesync conducted with displays that can refresh below 40Hz, we won't know that. Variable syncing doesn't work like V-Sync though, so I tend to think anything down to 30Hz would be plausible, esp considering those would likely be only momentary dips, not hovering at that range. If it hovers at that range consistently it's obvious we are talking a gamer who's tried to bite off more tech than they can afford on the GPU end of the spectrum.

Even if you're right though, you still somewhat substantiate my point, because even 40Hz is well below the current 48Hz limited displays that support Freesync. It was suggested in the Anandtech comparison review that for avid gamers buying into this kind of tech, 45-60 FPS would be the sweet spot to shoot for. For the average gamer looking for a new display and not minding the slight extra for a Freesync capable display, I would guess the acceptable range would be more likely 40-60 FPS. There's ALWAYS going to be new high stress games that push your hardware though, so it helps to have a display and sync tech that is flexible.

The point I've made consistently here though, is that reviews like the PC Per one only talk about performance based on tests limited to 48Hz on the Freesync side of the equation, which in itself is too biased and premature to even be comprehensive. Not accounting for lack of proper monitors to test with is quite unprofessional, esp for a site that calls themselves PC "Perspective". If anything it's NOT a perspective viewpoint.

 

[WhoDecidedThat]

the PC Per one only talk about performance based on tests limited to 48Hz on the Freesync side of the equation,

In their video, they clearly show the Free-Sync monitor working perfectly well till 39 Hz. They start seeing problems below that refresh rate.

 

[Xzibit]

In their video, they clearly show the Free-Sync monitor working perfectly well till 39 Hz. They start seeing problems below that refresh rate.

There argument is based on 3hz differences which doesn't involve VRRW at all.

Adaptive-Sync + FreeSync = 39hz cut off
G-Sync = 36hz cut off

There more hung up on the frame doubling aspect more then anything.

 

[arbiter]

At low FPS:
g-sync = better, at least esthetically, no idea if it ads lag or if you can sens this lag
freesync= under the refresh rate of the monitor is none existing

High FPS:
g-sync= it limits you to the refresh rate of the monitor
freesync= better (maybe), at list if you have the hardware to push the FPS it can go over the refresh rate of your monitor (better for competitive play)

At low FPS, it won't add lag. If say game is running 25fps, Freesync will go as low as 40hz refresh stop and stay there so you will get tearing. G-sync will double the refresh rate of panel to 50hz and show same image 2 times in a row. Reasons for this is panel can only go so long between the image refresh before you start getting flickering or even causing damage to the panel.

At high FPS, freesync yea does disable v-sync but you do get tearing which IMO defeats the point of even buying a VRR in the first place. Even with v-sync on at 144hz and input latency would only me like 7ms aka .007seconds so less you are a pro competitive gamers don't believe its gonna be an issue.

Honestly, the low frame rate thing is overblown. Look how long G-Sync has been on the market and how few manufacturers are supporting it. Freesync is relatively new and has already been adopted by VESA, which G-Sync hasn't mind you.

Freesync is a proprietary use of the adaptive sync spec that was adopted.

Yeah. A lot of people in forums are like, "It works at 9 Hz. G-Sync can't do that." I am like, "Who the bloody hell pays over 400$ for a monitor only to play below 25 Hz?" It's crazy!

The adaptive sync spec Allows for 9hz but problem is, No panel can go that low without damage or flickering.

No it doesn't. Do you think NVIDIA and AMD engineers are morons? You need a chip very close and properly attuned to the display to make frame doubling work. If frame doubling could be done properly in software NVIDIA and AMD would have done so already. But they haven't.

G-sync does do frame doubleing if you watched that video. G-sync module has 768mb of ram on it so it stores the frame data to do doubling. AMD will have to do it in their drivers.

There argument is based on 3hz differences which doesn't involve VRRW at all.

Adaptive-Sync + FreeSync = 39hz cut off
G-Sync = 36hz cut off

There more hung up on the frame doubling aspect more then anything.

freesync goes down to 40hz then stops and stays at that, g-sync starts to do double frame being show using last one it got. AMD would have to do that in driver. that 36hz cut off could be cause the panel, since they only have 1 g-sync in this can't confirm it.
They were showing using an old meter so show refresh rate of what tech does and how it reacts going down to low refresh rates.

If you're gaming at under 25-40fps, fu** the 'sync' monitor, get yourself a proper graphics card.

^ would second that, or turn some options down a bit.

 

[Xzibit]

freesync goes down to 40hz then stops and stays at that, g-sync starts to do double frame being show using last one it got. AMD would have to do that in driver. that 36hz cut off could be cause the panel, since they only have 1 g-sync in this can't confirm it.
They were showing using an old meter so show refresh rate of what tech does and how it reacts going down to low refresh rates.

That is the thing. Variable Refresh Rate between the two work the same. The difference is G-Sync module has a (Panel Self Refresh) algorithm/mechanism at the low end. Another thing they borrowed from the VESA standards.

What would be ideal is to make VESA eDP 1.4a standards compatible with stand alone monitors and we could have blur free, self refreshing, VRR monitors.

If you go back and look at VESA adaptive-sync promo

It could be these first modules don't have all the features yet either.

 

[MilkyWay]

Isn't frame doubling a problem for something like a 1st person shooter?

EDIT: I guess your going to have problems with FPS games at those lower frame rates anyway as its not updating as frequently.

 

[Frag_Maniac]

In their video, they clearly show the Free-Sync monitor working perfectly well till 39 Hz. They start seeing problems below that refresh rate.

It's not a 40Hz limitation of Freesync like you make it sound, it's because the monitor they used only went as low as 40Hz for VRR use. I wouldn't put a lot of stock in that one monitor though, esp since this tech is so new. OC.net has a review on a BenQ XL2730Z, which is SUPPOSED to have a 25Hz bottom end, but officially it only supports 40Hz-144Hz for VRR.

"As far as refresh rates are concerned the monitor appears to have a range of 25hz to 144hz while using the DP connection, using dual link dvi the monitor appears to be limited to 60hz at 2560x1440 which is unfortunate; since the big feature being freesync on this monitor, which is only supported using the DP connection, this is mostly a non-issue. I hope that this does in fact lead to the limits for freesync being 40-144hz or possibly 30-144 hz with this panel. The VRR range for this monitor is officially 40-144hz."

Source: http://www.overclock.net/t/1546860/first-hands-on-experience-with-benq-xl2730z

It's like when 120Hz monitors first came out, many were only sometimes OCable to that range, but didn't guarantee it.

I give credit for these guys trying to be honest and professional, but IMO they never look or sound it whenever I watch their videos, which is seldom. Just the fact that the guy on the right spent the first 40 sec talking like he was intimidated, then put off by an "analog" scope being used, was laughable. Trust me, there will be many more low refresh monitors made that support Freesync now that VESA has adopted it.

As I've said before, the main difference between these guys and more knowledgeable sites that actually HAVE techs, is the others have the insight to know this is just a temp issue common to any new tech that isn't fully supported yet. They claim they are the only ones pointing out the poor performance below the monitor's refresh range, but they aren't. Anandtech and others have noted it as well, but the difference is, they knew it was just a lack of suitable displays supporting it for now.

 

[Xzibit]

All they had to do is look at the website.

Benq XL2730Z Specifications

DP1.2a :
Input Hor. Frequency (KHz) = 222KHz

Input Ver. Frequency (Hz) = 40Hz ~ 144Hz

 

[WhoDecidedThat]

As I've said before, the main difference between these guys and more knowledgeable sites that actually HAVE techs, is the others have the insight to know this is just a temp issue common to any new tech that isn't fully supported yet.

They are pointing out the present issue. I don't remember them ever saying that this problem will remain going forward. It's common sense that this will no longer be a problem as tech matures.

 

[FordGT90Concept]

FreeSync uses VESA's Adaptive-Sync standard which is open and royalty free. I don't care if G-Sync has a better implementation currently, the Adaptive-Sync capabilities of DisplayPort 1.2a and newer are the way to go. NVIDIA should jump on the bandwagon. The last thing we need is monitors that only work with NVIDIA graphics cards. Monitors should be advertised as Adaptive-Sync or not, not FreeSync/G-SYNC. Until that happens, I'll pass.

That aside, it appears there is no argument: G-SYNC has the better implementation. Being able to go under a monitor's minimum refresh rate is far more important to me than being able to exceed its maximum.

 

[BiggieShady]

While gaming the important thing is consistence for suspension of disbelief to really work ... anything that yanks you out of the experience of "being there" is bad in my book.
So, g-sync more consistent approach seems better to me ... for now, at least, until panel manufacturers start making beefier

Holy sh*t Alan Malvantano looks like a paedo ...that stare..

Yeah. And the way he sits still. It's creepy. It's like he is a zombie or something.

It's you two who are creepy with these kind of remarks.

 

[Xzibit]

It sounds to me like there needs to be an open standard for Variable Refresh Rate. Having proprietary implementations from NVIDIA and AMD is ridiculous. I wouldn't buy either. I think variable refresh rate should be included in the 1.4 version of DisplayPort.

Standards are there since DP 1.2a.

Q: Is VESA’s new AdaptiveSync supported?
A: Yes. AdaptiveSync was first supported by DisplayPort 1.2a, and it is already supported in some available products. This is also branded as “Free-Sync” from AMD, which is based on VESA’s AdaptiveSync Standard.

Its hardware & feature support that needs to catch up.

DP 1.3 also included improved vblanking standards


AMDGaming on Twitter - We’re excited to welcome @ASUS and their new 27" WQHD gaming monitor to the #FreeSync family!

PCPerspective - ASUS MG279Q Monitor Now Officially a FreeSync Monitor

 

[Ebo]

The way I choose to look at it is.

AMD got the ball on this, since

1. Free sync is new and only a few screens have come out yet.

2. Free sync have allready been adopted by the top 3 screen manufactures

3. Its an open standard that dosent require a lot extra money for the manufacture to use instead of G-sync that needs extra hardware in the screen to work.

4. G-sync only works on Nvidia cards(as I understand it)

 

[arbiter]

3. Its an open standard that dosent require a lot extra money for the manufacture to use instead of G-sync that needs extra hardware in the screen to work.

4. G-sync only works on Nvidia cards(as I understand it)

3. Freesync is based on an open standard but still is AMD made solution using the standard in a proprietary way. Reason freesync only just came out was they needed a new hardware for the monitor to work, just like g-sync module.

4. freesync only work on certain AMD gpu's, (290(x), 260(x), 285, 295x2 for their dedicated).

There are a few issues freesync needs to address and work on, like ghosting issue it does have that doesn't happen in g-sync. No its not the panel that is the problem which most people jump on as the problem, its a voltage control issue that freesync monitors need to control better.

 

[Xzibit]

There are a few issues freesync needs to address and work on, like ghosting issue it does have that doesn't happen in g-sync. No its not the panel that is the problem which most people jump on as the problem, its a voltage control issue that freesync monitors need to control better.

TFTCentral reviews of G-Sync monitors say otherwise.

http://www.tftcentral.co.uk/images/acer_xb270hu/od_comparison2.jpg

http://www.tftcentral.co.uk/images/acer_xb270hu/pursuit_3.jpg

http://www.tftcentral.co.uk/images/acer_xb270hu/pursuit_overdrive.jpg

Adjusting the settings will improve it. At the same time it will increase the monitors Response Time.

It's been pointed out to Allyn in the comments and in other forums and he still hasnt had a response to why he made the comparison that the BenQ and Asus RoG Swift had the same panel nor why the LG was compared while its rated at a higher G2G.

They didnt even bother to test Response Timing of the panels. The assumption was if it said 1ms on the box they were equal. Thats the kind of comparison i'd expect from BestBuy or Walmart.

 

[metalslaw]

It's not a 40Hz limitation of Freesync like you make it sound, it's because the monitor they used only went as low as 40Hz for VRR use. I wouldn't put a lot of stock in that one monitor though, esp since this tech is so new. OC.net has a review on a BenQ XL2730Z, which is SUPPOSED to have a 25Hz bottom end, but officially it only supports 40Hz-144Hz for VRR.

While I get the gist of your posts, I just want to point out that the rog swift was also the first g-sync monitor out. So being it was the 'newest tech' at the time, this could be a fair comparison actually.

However, I believe that the freesync monitors will be great once they get the refresh rate down to the low 20's for the min. Don't know why you would want to game at that fps as the time between frames is horrendous, but to each his own (and I get why you would want it for some games that aren't fast twitch, but I come from a crt ftw background ).

But nvidia does have the better solution. Frame doubling is actually a great solution for low refresh rates, so until really low refresh rate freesync monitors come along, nvidia will be winning.

 

[arbiter]

But nvidia does have the better solution. Frame doubling is actually a great solution for low refresh rates, so until really low refresh rate freesync monitors come along, nvidia will be winning.

It would be something AMD would have to do in drivers, and tell monitor its 2x what it is. However if you have a monitor that is 40-75hz, well would be a bit hard to do that. IMO if are getting to that 40fps range, its time to cut down some graphic settings and bring that fps up a bit or buy a better video card.

 

[WhoDecidedThat]

tell monitor its 2x what it is.

If it were that simple, they'd have done it already.

 

[Xzibit]

Right now it doesn't seem Adaptive-Sync+FreeSync monitors have the buffer in the T-Con. At least no-one has open one up yet to confirm it. Adaptive-Sync+FreeSync doesn't need to do frame pacing prediction like G-Sync is doing to pace out the lower end frames in order to tell the buffer on the module when to insert the duplicate.

Adaptive-Sync+FreeSync just switches Off below VRR. Depending on your V-Sync on/off settings that's what you'll get

G-Sync switches to prediction mode below VRR to predict how to pace the duplicate frames.

Which I suspect is why G-Sync monitor still have that Flicker issue due to the prediction method. Where Adaptive-Sync+FreeSync monitors don't have that issue.

 

[Ikaruga]

Nice video!

They didn't mention that if AMD would do it in their drivers (from software), it would need to use VRAM to store the additional frames. I know it wouldn't be much ofc, but still... it could be important.

I personally find Nvidia's approach much more elegant again (and please believe me I'm not a fanboy of anybody, I would really love to like more something from AMD too, but it just not happening for almost a decade now, except their APUs perhaps:/). Low fps-dips are happening a lot(!) in gaming. I personally don't see much difference beyond 100-110fps (I play Quakeworld at 144Hz and there is a little bit more fluidity indeed, but nothing ground breaking I couldn't live without. I frag just as much with 100fps as with 144), but I see any low dips in any game immediately! If the monitor could really do a nice smooth transition like how Nvidia and this video claims, it will be one of the very best things happened in gaming tech for many years imho.

 

[Frag_Maniac]

But nvidia does have the better solution. Frame doubling is actually a great solution for low refresh rates, so until really low refresh rate freesync monitors come along, nvidia will be winning.

That's like saying Wonder has the better bread because it's sliced, and this other loaf in the brown bag that was just baked isn't.

When are you guys going to get a clue that it's not Freesync itself, it's that it's brand new and not fully supported yet hardware wise.

Once it is, there will be no comparison. Expensive G-Sync displays will be sitting on shelves with no one buying them, except for a handful of Nvidia elitist, and that's IF Nvidia remain stubborn about adopting Freesync.

And to those whom are siding with G-Sync for now, some even contradicting that by saying Nvidia should adopt Freesync, why are you acting like the min refresh is such a big deal? If it were really THAT hard to make lower refresh monitors than what are currently available, do you think VESA would have even adopted Freesync as a standard? VESA do their research, there is a LOT riding on their decisions. The standards they adopt can literally make or break certain businesses.

 

[MilkyWay]

Theres no reason Nvidia can't support adaptive sync (freesync), it's just that they refuse too.

 

[Ikaruga]

why are you acting like the min refresh is such a big deal? If it were really THAT hard to make lower refresh monitors than what are currently available, do you think VESA would have even adopted Freesync as a standard?

Sorry to be so curious, but do you even know what are you talking about? Why do you think there is a minimum refresh rate set for every LCD monitor in the market? You lit a pixel for too long on the panel without refreshing it and colors and whatnot starts to drift pretty bad. There is a minimum refresh rate there to ensure image quality (sorry to break it to you like this, but some of us still finds that important here). If technology will allow it, they will make monitors with lower minimum refresh-rates ofc, but that day is yet to come for the mainstream market. Until then, enjoy your jerkiness and judders because of fps drops in heavily multiplayer games.

 

[Xzibit]

Sorry to be so curious, but do you even know what are you talking about? Why do you think there is a minimum refresh rate set for every LCD monitor in the market? You lit a pixel for too long on the panel without refreshing it and colors and whatnot starts to drift pretty bad. There is a minimum refresh rate there to ensure image quality (sorry to break it to you like this, but some of us still finds that important here). If technology will allow it, they will make monitors with lower minimum refresh-rates ofc, but that day is yet to come for the mainstream market. Until then, enjoy your jerkiness and judders because of fps drops in heavily multiplayer games.

Just FYI.

The Asus RoG Swift is 50hz-144hz. You can say G-Sync is under driving it. The entire notion of not damaging the panel goes out the window when your operating it under the limits, does it not ?

 

[Ikaruga]

Just FYI.

The Asus RoG Swift is 50hz-144hz. You can say G-Sync is under driving it. The entire notion of damaging the panel goes out the window when your operating it under the limits, does it not ?

I never said damaging the panel anywhere, so idk why did you quoted my post. But to answer you, 50Hz is pretty far from what I was talking about, it would happen around 15-20Hz depending on the panel, but never the less, just one frame of a huge fps dip and you have "jump" on a FreeSync monitor. Don't get me wrong please, it's far from the end of the world ofc, I understand it's way blown out when you think about it like that, and I think Freesync is really great, props to AMD for taking a stand on the issue. All I'm saying (and said), if you compare the two technologies (on a tech enthusiast site like our beloved TPU): "I personally find Nvidia's approach much more elegant again".

 

[Xzibit]

I never said damaging the panel anywhere, so idk why did you quoted my post. But to answer you, 50Hz is pretty far from what I was talking about, it would happen around 15-20Hz depending on the panel, but never the less, just one frame of a huge fps dip and you have "jump" on a FreeSync monitor. Don't get me wrong please, it's far from the end of the world ofc, I understand it's way blown out when you think about it like that, and I think Freesync is really great, props to AMD for taking a stand on the issue. All I'm saying (and said), if you compare the two technologies (on a tech enthusiast site like our beloved TPU): "I personally find Nvidia's approach much more elegant again".

I was too vague I guess but it was on the line of comparisons

AdaptiveSyn+FreeSync work within the monitors limits 40-144hz or 48-75hz depending on monitor.

Gsync dips below the monitors limits 50-144hz. Your paying a $200 premium for your monitor to be under driven below spec (Which may have to do with all the quality control issues Asus had to deal with) which causes flickering and can be reproduced by taking in-game screenshots

EVE Online does this exact thing while taking an in-game screen shot, so we used that for our initial testing.

It would be ideal if at the minimal monitor hz a panel self-refresh would kick in but not exceed above the minimal variable refresh rate window. You'd eliminate the prediction G-Sync is doing along with the un desired dipping and spiking into the variable refresh rate window and its drawbacks.

The only thing left to add would be eDP 1.3 backlight control.

 

[Aquinus]

Interesting comparison, but most games don't run at a constant frame rate and the real question is how can FreeSync or GSync absorb smaller latency changes that occur a lot and to varying degrees as opposed to wide (and constant) changes that really are only momentary.

So while it was interesting, I don't think it's enough for me to say much of anything about one or the other. It's only an interesting observation.