ASUS VG279QM Input Lag Question [60 Hz Lag versus 240 Hz Lag]

[Chief Blur Buster]

Lots of people get confused by 60fps lag.

60fps at 60Hz on a 240Hz panel can sometimes be more laggy than 60fps at 60Hz on a native 60Hz panel

BUT

60fps at 240Hz on a 240Hz panel will be less laggy than 60fps at 60Hz on a native 60Hz panel.

This is the distinction. As long as the computer is outputting at 240Hz, the 60fps can stay low lag (for same sync technology versus sync technology, like VSYNC ON versus VSYNC ON, or VRR versus VRR, or VSYNC OFF versus VSYNC OFF).

[Jazzin]

Lots of people get confused by 60fps lag.

60fps at 60Hz on a 240Hz panel can sometimes be more laggy than 60fps at 60Hz on a native 60Hz panel

BUT

60fps at 240Hz on a 240Hz panel will be less laggy than 60fps at 60Hz on a native 60Hz panel.

This is the distinction. As long as the computer is outputting at 240Hz, the 60fps can stay low lag (for same sync technology versus sync technology, like VSYNC ON versus VSYNC ON, or VRR versus VRR, or VSYNC OFF versus VSYNC OFF).

Hi, I know this is an old post and you explained this very well.

So to clarify, consoles such as the Xbox Series X can run up to 120hz, but a vast majority of games can only run at 60fps.

So for the xbox series x, I wouldn't experience the large input lag on games that only run at 30/60fps as long as I have the console's refresh rate set to 120hz?

[andrelip]

60fps at 240Hz VRR is no problem: Silky Low Lag

Good news, VRR 60fps at 240Hz is always low lag. Not a problem.

60fps@240Hz VRR is amazingly low lag -- much lower lag than 60fps on low-lag 60Hz monitors.

If you run emulators or console ports, just make sure you stay at 240Hz VRR, and let the software cap itself to 60fps automatically. It'll be fine.

No problemo.

Advanced Explanation Of Why Fixed-Hz 60Hz Can Be Laggy On 240 Hz Panels

This is mainly relevant if you have to use a 60 Hz gaming console with a 240Hz monitor. This won't be a problem if you only use PC, and only use 240Hz.

If you've already seen my high speed videos of LCD refreshing, you'll see panels refresh top to bottom, one pixel at a time, at www.blurbusters.com/scanout

(Now, this is independent on a cable and on the panel, although they can be synchronized at the same speed)

Input lag 60 Hz on some 240Hz monitors is caused by a scanrate-converting scaler. (Scanrate = number of pixels rows per second, delivered sequentially over the cable, or refreshed to the panel). See diagrams here: Why 60 Hz Input latency Is High On Some 240 Hz Panels


Fortunately, you can kind of fix this via using a Quick Frame Transport trick, via using Vertical Total 4500 on a 60Hz signal (for times the regular Vertical Total 1125 for a 240Hz signal). You do need to combine this with RTSS Scanline Sync because Windows doesn't properly take advantage of Quick Frame Transport.


Other ASUS monitor models such as the XG248Q, is scanrate multisync, so it can do 60Hz low-lag properly:

Sorry to post again in this old thread. It has more than a year now and hundred of pages, so you should have know more about it.

1- When rtings and other sites declare high input lag using 60hz@VRR, do you think they refer to 60fps on a 280hz VRR or VRR with 60hz max frequency?
2- If the second, do you think 60fps @ 280hz in this type of monitor will be much worse than the other with dynamic speed?
3- The large VT trick works for this monitor?
4- Is there a way to create this model at the monitor level to use that in PS5?

[elexor]

1- When rtings and other sites declare high input lag using 60hz@VRR, do you think they refer to 60fps on a 280hz VRR or VRR with 60hz max frequency?

rtings test 60hz vrr not maxhz@60fps. pointless test you should be running your monitor at max refresh on a pc. enable vrr for 60fps content.

2- If the second, do you think 60fps @ 280hz in this type of monitor will be much worse than the other with dynamic speed?

If you enable gsync/vrr @280hz 60fps input lag will be better then a nativescanrate monitor.

3- The large VT trick works for this monitor?

Large VT's do work for this monitor but it's not needed you should just use gsync/vrr which has the same effect. custom VT's are more used for doing low hz strobing. elmbsync isn't good for low hz strobing on this monitor because overdrive is locked way too high. so in short don't worry about large Vt's it won't be useful for you.

4- Is there a way to create this model at the monitor level to use that in PS5 ​

Unfortunately no the ps5 is locked into 60hz when loading a 60fps game (vast majority games are 60fps). ps5 does not support VRR either making the vg279qm a bad choice for the ps5. xbox series x actually uses 120hz VRR with all games so you wouldn't have the lag problem.
maybe sony will release better firmware that will change things it's dumb the way it is right now.

[andrelip]

Thanks for the explanations. About the PS5 the idea would be to patch the Edid or something like this to force large VT on 1080p@60hz. I don’t know if that’s possible to flash and if the ps5 would support that move.

[elexor]

Thanks for the explanations. About the PS5 the idea would be to patch the Edid or something like this to force large VT on 1080p@60hz. I don’t know if that’s possible to flash and if the ps5 would support that move.

Even if it was possible to get a large VT mode working on ps5 you would see no lag benefit because it won't change the ps5's frame present behavior. on the pc you have to use scanline sync to do this. it's automatic for vrr.

[Chief Blur Buster]

Even if it was possible to get a large VT mode working on ps5 you would see no lag benefit because it won't change the ps5's frame present behavior. on the pc you have to use scanline sync to do this. it's automatic for vrr.

Do you have a citation for that?

It’s possible for a PS or XBox to happen to choose a frame presentation behavior that just happens to be favourable with Quick Frame Transport (QFT).

It’s unlikely though, that the consoles would use a custom mdoe that is QFT though; but it’s possible to the OS to already be using a frame presentation behavior already compatible with QFT. It’s a dice roll whether or not a specific platform may already be accidentally using a frame presentation workflow that is very compatible with QFT.

[elexor]

Do you have a citation for that?

No, my bad. I assumed it was highly unlikely.