Can G-Sync monitors do >60Hz, G-Sync and ULMB at lower resolutions ?

[Gryz]

In G-Sync monitors, the G-Sync module replaces the normal scaler. However, it seems that G-Sync monitors can still upscale. From the TFTCentral's Acer XB270HU review:

The screen is designed to run at its native resolution of 2560 x 1440 and at a 60Hz recommended refresh rate. However, if you want you are able to run the screen outside of this resolution. We tested the screen at a lower 1920 x 1080 resolution to see how the screen handles the interpolation of the resolution, while maintaining the same aspect ratio of 16:9.

There is no more specific information about resolutions in that review. In TFTCentral's Asus ROG Swift's review there is more information. They show a list of supported non-native resolutions. (Search for "Operating Modes and Graphics Card Considerations" if the jpg below doesn't show).

There are a number of smaller resolutions (less pixels) mentioned. What surprised me is that 1280x720 is not a supported non-native resolution. Weird, as 720p is exactly half of 1440p. Also, that table shows 60Hz at all non-native resolutions. I would like to run some (heavy) games in 720p on a G-Sync monitor, so I can run 100Hz ULMB at 720p. This table seems to indicate that that would not be possible.

Can anyone with a G-Sync monitor confirm or deny my following questions ? Testing to be sure would be awesome.

1) Can you set your G-Sync monitor to 85/100/120/144 Hz in any (smaller) non-native resolution ?
2) Can you use ULMB in any non-native resolution ?
3) Can you use G-Sync in any non-native resolution ?
4) Can you pick any non-native resolution, or is there a limited amount of preset resolutions you can pick from ?
5) If you have a 1440p monitor, is 1280x720 allowed and working ?

Edit: question about DSR removed. DSR was only supported on Maxwell, but is supported on older monitors now too. I guess my game can render at any resolution, my GPU upscales the frame to 1440p. And my monitor isn't aware of anything, and just receives a 1440p signal. And then can do 144Hz, G-Sync or ULMB. So it seems possible what I want. Would be easier if the monitor could do the upscaling too.

Thanks in advance.

 

[Gryz]

500 Views, and no answers.
Weird. Either my questions are so dumb, that it wasn't worth answering them. Or nobody has tested this.

I got my Acer XB270HU yesterday.
So I could do some testing myself.
The whole issue is a lot easier than I thought.

1) Yes, I could run games in non-native resolution, at higher framerates. It seems that the XB270HU does scale its input to its native resolution fine. Without the need for the user to do anything. And for the few tests I've done in games, that even works with refreshrates above 60 Hz.

2) Yes, I used ULMB at 1280x720 at 100Hz fine. The displayed image does noticably get pixelated. More than I expected. So I will probably not run demanding games at 720p with ULMB.

3) I haven't tested G-Sync with 720p yet. But I'm convinced now that will work too.

4) It seems the limiting factor in resolutions are the games. Not the monitor or the drivers. Especially UnrealEngine-based games do not seem to support all the resolutions you'd expect. Even new games. And editing the config-files does not always work.

5) Even though 720p was not mentioned in TFTCentral's list, it does not seem to be handled different from other resolutions.

 

[Black Octagon]

Would test if I had such a monitor, but I don't.

If you don't get any replies, I suggest you post this same thread on [H] and/or BlurBusters. AT VC&D discussion is far more focused on GPUs than monitors.

 

[JoeRambo]

The only problem with Gsync not working is in Unity engine games. But that is pretty much expected, since they are not fullscreen (a requirement for Gsync), but rather dirty magic window mode. So Wasteland2, Pillars won't run with Gsync.

 

[OlyAR15]

Personally, I've never run any LCD or other fixed-resolution display in anything other than its native resolution. So I've never tested my monitor in other resolutions and just can't be bothered. In fact, I can't think of a good reason why you would run a non-native resolution on a monitor.

 

[Gryz]

In fact, I can't think of a good reason why you would run a non-native resolution on a monitor.

Because a game might run 30-40 fps @1440p, and 120 fps @720p. 30-40 fps with G-Sync is far from smooth. And if you want to run ULMB, then you need 85/100/120Hz. I rather have a smooth game in lower resolution, than a stuttery game in higher resolution.

All of my questions have been resolved. By myself. I decided to post my own answers to my own questions, so that someone else who is pondering buying a G-Sync/ULMB monitor can find this information.

G-Sync and ULMB work at all resolutions, even when they are not the native resolution.

Unfortunately not all games seem to support resolutions higher than 1920x1200. And also, many games don't seem to go above 60fps, unless you mess with their config files.

 

[kasakka]

G-Sync displays use the GPU for upscaling. Unfortunately in my experience the algorithms Nvidia use for upscaling are nowhere near as good as what dedicated display scalers have. When I had a Dell 3008WFP (2560x1600) there was a marked difference between GPU vs display scaling. The Dell was much sharper at 1080p.

On my ASUS Swift 1080p looks acceptable but personally I decided to invest in enough GPU horsepower to run anything at the native 1440p.

DSR and MFAA only work with a single card when using a G-Sync display at the moment. SLI+DSR works as well but when a G-Sync monitor is connected, DSR is disabled on SLI. It's a ridiculous artificial limitation as I'd rather be able to use ULMB+DSR if G-Sync and DSR won't work.