NVIDIA G-Sync for Notebooks Announced, No Module Required

Subject: Displays, Mobile | May 31, 2015 - 06:00 PM |
Tagged: nvidia, notebooks, msi, mobile, gsync, g-sync, asus

If you remember back to January of this year, Allyn and posted an article that confirmed the existence of a mobile variant of G-Sync thanks to a leaked driver and an ASUS G751 notebook. Rumors and speculation floated around the Internet ether for a few days but we eventually got official word from NVIDIA that G-Sync for notebooks was a real thing and that it would launch "soon." Well we have that day here finally with the beginning of Computex.


G-Sync for notebooks has no clever branding, no "G-Sync Mobile" or anything like that, so discussing it will be a bit more difficult since the technologies are different. Going forward NVIDIA claims that any gaming notebook using NVIDIA GeForce GPUs will be a G-Sync notebook and will support all of the goodness that variable refresh rate gaming provides. This is fantastic news as notebook gaming is often at lower frame rates than you would find on a desktop PC because of lower powered hardware yet comparable (1080p, 1440p) resolution displays.


Of course, as we discovered in our first look at G-Sync for notebooks back in January, the much debated G-Sync module is not required and will not be present on notebooks featuring the variable refresh technology. So what gives? We went over some of this before, but it deserves to be detailed again.

NVIDIA uses the diagram above to demonstrate the complication of the previous headaches presented by the monitor and GPU communication path before G-Sync was released. You had three different components: the GPU, the monitor scalar and the monitor panel that all needed to work together if VRR was going to become a high quality addition to the game ecosystem. 


NVIDIA's answer was to take over all aspects of the pathway for pixels from the GPU to the eyeball, creating the G-Sync module and helping OEMs to hand pick the best panels that would work with VRR technology. This helped NVIDIA make sure it could do things to improve the user experience such as implementing an algorithmic low-frame-rate, frame-doubling capability to maintain smooth and tear-free gaming at frame rates under the panels physical limitations. It also allows them to tune the G-Sync module to the specific panel to help with ghosting and implemention variable overdrive logic. 


All of this is required because of the incredible amount of variability in the monitor and panel markets today.


But with notebooks, NVIDIA argues, there is no variability at all to deal with. The notebook OEM gets to handpick the panel and the GPU directly interfaces with the screen instead of passing through a scalar chip. (Note that some desktop monitors like the ever popular Dell 3007WFP did this as well.)  There is no other piece of logic in the way attempting to enforce a fixed refresh rate. Because of that direct connection, the GPU is able to control the data passing between it and the display without any other logic working in the middle. This makes implementing VRR technology much more simple and helps with quality control because NVIDIA can validate the panels with the OEMs.


As I mentioned above, going forward, all new notebooks using GTX graphics will be G-Sync notebooks and that should solidify NVIDIA's dominance in the mobile gaming market. NVIDIA will be picking the panels, and tuning the driver for them specifically, to implement anti-ghosting technology (like what exists on the G-Sync module today) and low frame rate doubling. NVIDIA also claims that the world's first 75 Hz notebook panels will ship with GeForce GTX and will be G-Sync enabled this summer - something I am definitely looking forward to trying out myself.

Though it wasn't mentioned, I am hopeful that NVIDIA will continue to allow users the ability to disable V-Sync at frame rates above the maximum refresh of these notebook panels. With most of them limited to 60 Hz (but this applies to 75 Hz as well) the most demanding gamers are going to want that same promise of minimal latency.


At Computex we'll see a handful of models announced with G-Sync up and running. It should be no surprise of course to see the ASUS G751 with the GeForce GTX 980M GPU on this list as it was the model we used in our leaked driver testing back in January. MSI will also launch the GT72 G with a 1080p G-Sync ready display and GTX 980M/970M GPU option. Gigabyte will have a pair of notebooks: the Aorus X7 Pro-SYNC with GTX 970M SLI and a 1080p screen as well as the Aorus X5 with a pair of GTX 965M in SLI and a 3K resolution (2560x1440) screen. 

This move is great for gamers and I am eager to see what the resulting experience is for users that pick up these machines. I have long been known as a proponent of variable refresh displays and getting access to that technology on your notebook is a victory for NVIDIA's team.

Podcast #350 - AMD's plan for HBM, IPS G-SYNC, GameWorks and The Witcher 3, and more!

Subject: Editorial | May 21, 2015 - 03:34 PM |
Tagged: podcast, video, amd, hbm, Fiji, g-sync, ips, XB270HU, corsair, Oculus, supermicro, asus, gladius, jem davies, arm, mali

PC Perspective Podcast #350 - 05/21/2015

Join us this week as we discuss AMD's plan for HBM, IPS G-SYNC, GameWorks and The Witcher 3, and more!

You can subscribe to us through iTunes and you can still access it directly through the RSS page HERE.

The URL for the podcast is: http://pcper.com/podcast - Share with your friends!

  • iTunes - Subscribe to the podcast directly through the iTunes Store
  • RSS - Subscribe through your regular RSS reader
  • MP3 - Direct download link to the MP3 file

Hosts: Ryan Shrout, Jeremy Hellstrom, Josh Walrath, and Allyn Malventano

Subscribe to the PC Perspective YouTube Channel for more videos, reviews and podcasts!!

Subject: Displays
Manufacturer: Acer

Introduction and Specifications

Displays have been a hot item as of late here at PC Perspective. Today we are looking at the new Acer XB270HU. In short, this is an IPS version of the ASUS ROG Swift. For the long version, it is a 1440P, 144Hz, G-Sync enabled 27 inch display. This is the first G-Sync display released with an IPS panel, which is what makes this release such a big deal. Acer has been pushing hard on the display front, with recent releases of the following variable refresh capable displays:

  • XB270H 27in 1080P 144Hz G-Sync
  • XB280HK 28in 4K 60Hz G-SYnc
  • XG270HU 27in 1440P 40-144Hz FreeSync
  • XB270HU 27in 1440P 144Hz G-Sync < you are here

The last entry in that list is the subject of todays review, and it should look familiar to those who have been tracking Acer's previous G-Sync display releases:


Here's our video overview of this new display. I encourage you to flip through the review as there are more comparison pictures and information to go along.

Continue reading our review of the Acer XB270HU 1440P 144Hz IPS G-Sync Monitor!!

Report: Acer XR341CKA 21:9 G-SYNC Monitor Has Multiple Inputs

Subject: Displays | April 16, 2015 - 10:26 AM |
Tagged: 3440x1440, XR341CKA, ultra-widescreen, gaming monitor, g-sync, acer, 21:9, ips

Acer's upcoming ultra-widescreen 34-inch G-SYNC gaming monitor, the XR341CKA, will have multiple inputs according to a report published by TFT Central, which indicates possible changes to the G-SYNC V2 module as previous displays only provided one input.


The Acer XR341CKA (Credit: TFT Central)

The Acer XR341CKA is a variant of the XR341CK, a FreeSync monitor that contains an identical panel. The IPS panel in both monitors is rated up to 75Hz refresh with a resolution of 3440x1440, and a contrast ratio of 1000:1 with 8-bit + FRC (effective 10-bit) color depth. The big story here is of course the G-SYNC module, and though we don't know the specific implementation yet is will be interesting to see what the input support of version 2 G-SYNC displays will be. According to TFT Central the FreeSync (CK) variant of the XR341 offers "HDMI 2.0 (MHL), DisplayPort, Mini DP and DP out connections," and "it will support daisy chaining via the DP out port and also PiP and PbP functions".


The original G-SYNC module (Credit: NVIDIA)

In contrast the G-SYNC variant (CKA) of the XR341 offers "DisplayPort, but also an additional HDMI 1.4 video connection...(and) will also support ULMB (Ultra Low Motion Blur)." TFT Central points out that this detail "would mark the first G-sync screen we've seen with more than one connection, so we will be interested to see how this works." If indeed this is a single module solution it is possible that NVIDIA has made changes with the second-gen G-SYNC module to allow for more than one input. We will have to wait and see, unless more details about this V2 module are forthcoming.

Source: TFT Central

Podcast #343 - DX12 Performance, Dissecting G-SYNC and FreeSync, Intel 3D NAND and more!

Subject: General Tech | April 2, 2015 - 01:16 PM |
Tagged: podcast, video, dx12, 3dmark, freesync, g-sync, Intel, 3d nand, 20nm, 28nm, micron, nvidia, shield, Tegra X1, raptr, 850 EVO, msata, M.2

PC Perspective Podcast #343 - 04/02/2015

Join us this week as we discuss DX12 Performance, Dissecting G-SYNC and FreeSync, Intel 3D NAND and more!

You can subscribe to us through iTunes and you can still access it directly through the RSS page HERE.

The URL for the podcast is: http://pcper.com/podcast - Share with your friends!

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  • MP3 - Direct download link to the MP3 file

Hosts:Ryan Shrout, Jeremy Hellstrom, Josh Walrath, and Allyn Malventano

Subscribe to the PC Perspective YouTube Channel for more videos, reviews and podcasts!!

Manufacturer: Various

It's more than just a branding issue

As a part of my look at the first wave of AMD FreeSync monitors hitting the market, I wrote an analysis of how the competing technologies of FreeSync and G-Sync differ from one another. It was a complex topic that I tried to state in as succinct a fashion as possible given the time constraints and that the article subject was on FreeSync specifically. I'm going to include a portion of that discussion here, to recap:

First, we need to look inside the VRR window, the zone in which the monitor and AMD claims that variable refresh should be working without tears and without stutter. On the LG 34UM67 for example, that range is 48-75 Hz, so frame rates between 48 FPS and 75 FPS should be smooth. Next we want to look above the window, or at frame rates above the 75 Hz maximum refresh rate of the window. Finally, and maybe most importantly, we need to look below the window, at frame rates under the minimum rated variable refresh target, in this example it would be 48 FPS.

AMD FreeSync offers more flexibility for the gamer than G-Sync around this VRR window. For both above and below the variable refresh area, AMD allows gamers to continue to select a VSync enabled or disabled setting. That setting will be handled as you are used to it today when your game frame rate extends outside the VRR window. So, for our 34UM67 monitor example, if your game is capable of rendering at a frame rate of 85 FPS then you will either see tearing on your screen (if you have VSync disabled) or you will get a static frame rate of 75 FPS, matching the top refresh rate of the panel itself. If your game is rendering at 40 FPS, lower than the minimum VRR window, then you will again see the result of tearing (with VSync off) or the potential for stutter and hitching (with VSync on).

But what happens with this FreeSync monitor and theoretical G-Sync monitor below the window? AMD’s implementation means that you get the option of disabling or enabling VSync.  For the 34UM67 as soon as your game frame rate drops under 48 FPS you will either see tearing on your screen or you will begin to see hints of stutter and judder as the typical (and previously mentioned) VSync concerns again crop their head up. At lower frame rates (below the window) these artifacts will actually impact your gaming experience much more dramatically than at higher frame rates (above the window).

G-Sync treats this “below the window” scenario very differently. Rather than reverting to VSync on or off, the module in the G-Sync display is responsible for auto-refreshing the screen if the frame rate dips below the minimum refresh of the panel that would otherwise be affected by flicker. So, in a 30-144 Hz G-Sync monitor, we have measured that when the frame rate actually gets to 29 FPS, the display is actually refreshing at 58 Hz, each frame being “drawn” one extra instance to avoid flicker of the pixels but still maintains a tear free and stutter free animation. If the frame rate dips to 25 FPS, then the screen draws at 50 Hz. If the frame rate drops to something more extreme like 14 FPS, we actually see the module quadruple drawing the frame, taking the refresh rate back to 56 Hz. It’s a clever trick that keeps the VRR goals and prevents a degradation of the gaming experience. But, this method requires a local frame buffer and requires logic on the display controller to work. Hence, the current implementation in a G-Sync module.

As you can see, the topic is complicated. So Allyn and I (and an aging analog oscilloscope) decided to take it upon ourselves to try and understand and teach the implementation differences with the help of some science. The video below is where the heart of this story is focused, though I have some visual aids embedded after it.

Still not clear on what this means for frame rates and refresh rates on current FreeSync and G-Sync monitors? Maybe this will help.

Continue reading our story dissecting NVIDIA G-Sync and AMD FreeSync!!

Subject: Displays
Manufacturer: AMD

What is FreeSync?

FreeSync: What began as merely a term for AMD’s plans to counter NVIDIA’s launch of G-Sync (and mocking play on NVIDIA’s trade name) has finally come to fruition, keeping the name - and the attitude. As we have discussed, AMD’s Mantle API was crucial to pushing the industry in the correct and necessary direction for lower level APIs, though NVIDIA’s G-Sync deserves the same credit for recognizing and imparting the necessity of a move to a variable refresh display technology. Variable refresh displays can fundamentally change the way that PC gaming looks and feels when they are built correctly and implemented with care, and we have seen that time and time again with many different G-Sync enabled monitors at our offices. It might finally be time to make the same claims about FreeSync.

But what exactly is FreeSync? AMD has been discussing it since CES in early 2014, claiming that they would bypass the idea of a custom module that needs to be used by a monitor to support VRR, and instead go the route of open standards using a modification to DisplayPort 1.2a from VESA. FreeSync is based on AdaptiveSync, an optional portion of the DP standard that enables a variable refresh rate courtesy of expanding the vBlank timings of a display, and it also provides a way to updating EDID (display ID information) to facilitate communication of these settings to the graphics card. FreeSync itself is simply the AMD brand for this implementation, combining the monitors with correctly implemented drivers and GPUs that support the variable refresh technology.


A set of three new FreeSync monitors from Acer, LG and BenQ.

Fundamentally, FreeSync works in a very similar fashion to G-Sync, utilizing the idea of the vBlank timings of a monitor to change how and when it updates the screen. The vBlank signal is what tells the monitor to begin drawing the next frame, representing the end of the current data set and marking the beginning of a new one. By varying the length of time this vBlank signal is set to, you can force the monitor to wait any amount of time necessary, allowing the GPU to end the vBlank instance exactly when a new frame is done drawing. The result is a variable refresh rate monitor, one that is in tune with the GPU render rate, rather than opposed to it. Why is that important? I wrote in great detail about this previously, and it still applies in this case:

The idea of G-Sync (and FreeSync) is pretty easy to understand, though the implementation method can get a bit more hairy. G-Sync (and FreeSync) introduces a variable refresh rate to a monitor, allowing the display to refresh at wide range of rates rather than at fixed intervals. More importantly, rather than the monitor dictating what rate this refresh occurs at to the PC, the graphics now tells the monitor when to refresh in a properly configured G-Sync (and FreeSync) setup. This allows a monitor to match the refresh rate of the screen to the draw rate of the game being played (frames per second) and that simple change drastically improves the gaming experience for several reasons.


Gamers today are likely to be very familiar with V-Sync, short for vertical sync, which is an option in your graphics card’s control panel and in your game options menu. When enabled, it forces the monitor to draw a new image on the screen at a fixed interval. In theory, this would work well and the image is presented to the gamer without artifacts. The problem is that games that are played and rendered in real time rarely fall into a very specific frame rate. With only a couple of exceptions, games frame rates will fluctuate based on the activity happening on the screen: a rush of enemies, a changed camera angle, an explosion or falling building. Instantaneous frame rates can vary drastically, from 30, to 60, to 90, and force the image to be displayed only at set fractions of the monitor's refresh rate, which causes problems.

Continue reading our first impressions of the newly released AMD FreeSync technology!!

BenQ's 24" XL2420G; affordable G-SYNC?

Subject: Displays | February 6, 2015 - 03:49 PM |
Tagged: XL2420G, NVIDA, g-sync, benq, 24

On Amazon the BenQ XL2420G is $540, or $529 from B&H Photo, not inexpensive but within the grasp of more people than some of the larger and more expensive G-SYNC monitors.  It has a maximum refresh rate of 144Hz as you expect from this style of monitor and it does indeed support Nvidia's 3D Vision, although some may be deterred by the 1080p resolution and the fact that it is a TN panel.  Some features do need to be sacrificed to bring the price down and the simple fact is that there are no IPS G-SYNC monitors currently for sale and TN is the faster type of monitor and this display is all about speed.  The Tech Report tried it out and were very impressed, check the full review to see why.


"Today, we're turning our attention to BenQ's XL2420G, a 24" G-Sync monitor that's currently selling for about $580 at Newegg. This display is a little smaller and more affordable than some of the other G-Sync offerings we've looked at, but it's not lacking in functionality or connectivity. Quite the opposite."

Here are some more Display articles from around the web:


Podcast #335 - Mobile G-Sync, GTX 970 SLI, a Broadwell Brix and more!

Subject: General Tech | February 5, 2015 - 02:05 PM |
Tagged: podcast, video, g-sync, GTX 970, gigabyte, brix s, broadwell-u, Intel, nuc, arm, Cortex-A72, mediatek, amd, Godavari, Raspberry Pi, windows 10

PC Perspective Podcast #335 - 02/05/2015

Join us this week as we discuss Mobile G-Sync, GTX 970 SLI, a Broadwell Brix and more!

You can subscribe to us through iTunes and you can still access it directly through the RSS page HERE.

The URL for the podcast is: http://pcper.com/podcast - Share with your friends!

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  • MP3 - Direct download link to the MP3 file

Hosts: Ryan Shrout, Jeremy Hellstrom, Josh Walrath, and Allyn Malventano

Subscribe to the PC Perspective YouTube Channel for more videos, reviews and podcasts!!


Manufacturer: NVIDIA


It has been an abnormal week for us here at PC Perspective. Our typical review schedule has pretty much flown out the window, and the past seven days have been filled with learning, researching, retesting, and publishing. That might sound like the norm, but in these cases the process was initiated by tips from our readers. Last Saturday (24 Jan), a few things were brewing:

We had to do a bit of triage here of course, as we can only research and write so quickly. Ryan worked the GTX 970 piece as it was the hottest item. I began a few days of research and testing on the 840 EVO slow down issue reappearing on some drives, and we kept tabs on that third thing, which at the time seemed really farfetched. With those two first items taken care of, Ryan shifted his efforts to GTX 970 SLI testing while I shifted my focus to finding out of there was any credence to this G-Sync laptop thing.

A few weeks ago, an ASUS Nordic Support rep inadvertently leaked an interim build of the NVIDIA driver. This was a mobile driver build (version 346.87) focused at their G751 line of laptops. One recipient of this driver link posted it to the ROG forum back on the 20th. A fellow by the name Gamenab, owning the same laptop cited in that thread, presumably stumbled across this driver, tried it out, and was more than likely greeted by this popup after the installation completed:

gsync panel connected-.png

Now I know what you’re thinking, and it’s probably the same thing anyone would think. How on earth is this possible? To cut a long story short, while the link to the 346.87 driver was removed shortly after being posted to that forum, we managed to get our hands on a copy of it, installed it on the ASUS G751 that we had in for review, and wouldn’t you know it we were greeted by the same popup!

Ok, so it’s a popup, could it be a bug? We checked NVIDIA control panel and the options were consistent with that of a G-Sync connected system. We fired up the pendulum demo and watched the screen carefully, passing the machine around the office to be inspected by all. We then fired up some graphics benchmarks that were well suited to show off the technology (Unigine Heaven, Metro: Last Light, etc), and everything looked great – smooth steady pans with no juddering or tearing to be seen. Ken Addison, our Video Editor and jack of all trades, researched the panel type and found that it was likely capable of 100 Hz refresh. We quickly dug created a custom profile, hit apply, and our 75 Hz G-Sync laptop was instantly transformed into a 100 Hz G-Sync laptop!

Ryan's Note: I think it is important here to point out that we didn't just look at demos and benchmarks for this evaluation but actually looked at real-world gameplay situations. Playing through Metro: Last Light showed very smooth pans and rotation, Assassin's Creed played smoothly as well and flying through Unigine Heaven manually was a great experience. Crysis 3, Battlefield 4, etc. This was NOT just a couple of demos that we ran through - the variable refresh portion of this mobile G-Sync enabled panel was working and working very well.

custom hz--.png

At this point in our tinkering, we had no idea how or why this was working, but there was no doubt that we were getting a similar experience as we have seen with G-Sync panels. As I digested what was going on, I thought surely this can’t be as good as it seems to be… Let’s find out, shall we?

Continue reading our story on Mobile G-Sync and impressions of our early testing!!