Freesync w/blur reduction, what is the advantage?

[amddude]

I just upgraded from the non-freesync 144hz benq with their blur reduction to an Acer XG270HU. The Acer is freesync but does not have blur reduction.

I'm noticing some ghosting but I know that's a driver issue. It seems 'smoother' but not as 'fast' as my old monitor, which is kinda bumming me. This has let me to wonder if the XL2703Z (benq, with the blur reduction) is a significantly better choice.

What I'm a tad confused about, this being my first freesync experience, is what exactly blur reduction does when in conjunction with freesync? Or is blur reduction mutually exclusive from freesync?

I'd appreciate any input.

 

[Flapdrol1337]

benq blur reduction is backlight strobing, can't do strobing and freesync at the same time.

Freesync should be smoother, strobing should be much sharper in motion.

 

[Stuka87]

Be sure you have the freesync enabled driver.

What video card do you have?

 

[amddude]

be sure you have the freesync enabled driver.

What video card do you have?

290 15.4.1

and freesync is enabled of course, as is overdrive

 

[96Firebird]

You should see less blur when FreeSync and Acer's overdrive work together, but right now they are still having issues:

From a monitor point of view the use of FreeSync creates a problem at the moment on the XG270HU at the moment, just as it had on the BenQ XL2730Z we tested recently. The issue is that the OD (overdrive) setting does nothing when you connect the screen over DisplayPort to a FreeSync system. This applies whether you are actually using FreeSync or not, you don't even need to have the option ticked in the graphics card settings for the problem to occur. As a result, the OD setting appears to be in the off state, and changing it to Normal or Extreme in the menu makes no difference to real-World response times or performance. As a result, response times are fairly slow at ~7.7ms G2G and there is a more noticeable blur to the moving image. See the more detailed response time tests in the previous sections for more information, but needless to say this is not the optimum OD (response time) setting on this screen. For some reason, the combination of FreeSync support and this display disables the OD function.

This only happens when you are using a FreeSync enabled graphics card, FreeSync capable drivers and the DisplayPort interface. If you switch to DVI or any other interface (which don't support the FreeSync feature) even from the same graphics card/driver then OD behaves as it should again. If you use DisplayPort but revert to an older non-FreeSync enabled driver package then OD works as it should. If you use a non-FreeSync supporting AMD card, or a card from NVIDIA/Intel then OD functions as it should. It's only when all 3 things are combined that the problem seems to occur. Obviously if you eliminate one of them to make OD work properly, you lose the advantage of FreeSync dynamic refresh rate control.

We know from our review of the BenQ XL2730Z, and our conversations with them about it that the issue is a known bug which apparently currently affects all FreeSync monitors. The AMD FreeSync command disturbs the response time function, causing it to switch off. It's something which will require an update from AMD to their driver behaviour, which they are currently working on. It will also require a firmware update for the screen itself to correct the problem. We know that AMD are working on their updated drivers, and we've asked Acer for comment on how they might handle firmware and screen updates.

Assuming that fixes the issue the performance when using a FreeSync system should be better than now, as you can move from OD Off to the better OD Normal setting. At the moment if you use the FreeSync function, or even just have a FreeSync enabled system in place, the response times are slower than they should be by a fair amount, and so you will experience a moderate amount of blur. To be fair they aren't really slow (7.7ms G2G measured) but they just aren't as fast as they could be and show some more noticeable blurring than OD normal. If you need to, you can always switch to DVI or another interface other than DisplayPort to benefit from the OD setting (but lose FreeSync).

We will update this review section when we know more about a fix for this issue.

Source

Now, with that in mind, I doubt you will be able to get the feel of BenQ's blur reduction with the XG270HU. As of right now, there are no monitors that can do variable refresh alongside strobing.

 

[amddude]

You should see less blur when FreeSync and Acer's overdrive work together, but right now they are still having issues:



Source

Now, with that in mind, I doubt you will be able to get the feel of BenQ's blur reduction with the XG270HU. As of right now, there are no monitors that can do variable refresh alongside strobing.

Ok so, it's just a difference in feel and I need to give the drivers time. Fair enough.

Thanks for your help guys I really appreciate it.

 

[BFG10K]

You should see less blur when FreeSync and Acer's overdrive work together, but right now they are still having issues:

Blur reduction and overdrive are completely different things.

 

[Dribble]

Blur reduction and overdrive are completely different things.

Well overdrive reduces blur. Last I heard it didn't work when freesync variable sync was working, one of several problems with the first gen of freesync monitors.

 

[BFG10K]

Well overdrive reduces blur.

So does a high refresh rate, but it's equally irrelevant to the OP.

 

[96Firebird]

Check the parts I bolded...

 

[Dribble]

So does a high refresh rate, but it's equally irrelevant to the OP.

/me Looks at op's first post which is all about blur and ghosting with new freesync monitor and wonders how the fact overdrive blur reduction does not work is irrelevant?

 

[3DVagabond]

Looks to me he was talking about using blur reduction. Which BenQ has but the Acer doesn't. OD speeds up the pixels response time, but it doesn't make as big of a difference as strobe type blur reduction which doesn't work with any type of variable refresh rate.

OD doesn't make any where near as big of a difference as people are portraying it to do. It does reduce ghosting to an extent. If overdone though it can create ghosting and artifacts, though.

I honestly believe it's blur reduction that the OP is missing. Unfortunately, the Acer doesn't offer it. Likely because it doesn't work with VRR anyway so it's not as critical to have with a Freesync (or a Gsync) monitor. Assuming you bought it to use VRR.

 

[Black Octagon]

If you went from a monitor with blur reduction to one without it, then you will notice a significant increase in blur/ghosting, REGARDLESS of refresh rate, variable refresh, overdrive or anything else.

Assuming, of course, that you were (properly) using your old monitor's blur reduction mode

 

[BFG10K]

/me Looks at op's first post which is all about blur and ghosting with new freesync monitor and wonders how the fact overdrive blur reduction does not work is irrelevant?

"Overdrive blur reduction" doesn't exist. It's something you made up. You're confusing the thread by nonsensically mixing terms like that.

The OP isn't missing overdrive; he's missing blur reduction.

Again, repeat after me: overdrive and blur reduction are completely different things.

 

[hawtdawg]

IMO they're doing freesync/gsync wrong with the 144hz monitors. They could offer blur reduction and variable refresh-rates if they simply doubled frames once the framerate dropped below 72. IE 71 fps would have doubled frames at 142hz etc, instead of having the monitor drop all the way down to 40hz. Gsync already does this once it gets below 40hz, not sure why they simply don't do it once it drops below 72hz. 72hz on a CRT did not present any noticeable flicker for the vast majority of people, unlike 60hz. Strobing would work fine at 72hz.

As much as i like the idea of freesync/gsync, the first revision of this technology isn't quite there yet imo.

 

[Black Octagon]

IMO they're doing freesync/gsync wrong with the 144hz monitors. They could offer blur reduction and variable refresh-rates if they simply doubled frames once the framerate dropped below 72. IE 71 fps would have doubled frames at 142hz etc, instead of having the monitor drop all the way down to 40hz. Gsync already does this once it gets below 40hz, not sure why they simply don't do it once it drops below 72hz. 72hz on a CRT did not present any noticeable flicker for the vast majority of people, unlike 60hz. Strobing would work fine at 72hz.

As much as i like the idea of freesync/gsync, the first revision of this technology isn't quite there yet imo.

Combining variable refresh and strobing backlight-driven blur reduction are two things that at present cannot be run simultaneously. I have ZERO doubts that manufacturers would have pounced on such an opportunity already were it truly reliable

 

[hawtdawg]

Combining variable refresh and strobing backlight-driven blur reduction are two things that at present cannot be run simultaneously. I have ZERO doubts that manufacturers would have pounced on such an opportunity already were it truly reliable

They can't with the way freesync and gsync currently work, which is what I was I was talking about. Currently freesync/gsync will drop the refresh rate of the monitor all the way down to 40hz, which is way too low for strobbing. I just explained this.

 

[Black Octagon]

They can't with the way freesync and gsync currently work, which is what I was I was talking about. Currently freesync/gsync will drop the refresh rate of the monitor all the way down to 40hz, which is way too low for strobbing. I just explained this.

Yes, that much is correct. But even apart from that, with variable refresh you have constantly changing screen refresh intervals. To combine such intervals with strobing, the monitor would need to constantly change the timing of the backlight activation and deactivation. Very complex, and even if you could get it to work, doing so at constantly changing intervals would result in constant variations in perceived monitor brightness. With strobing today, many users complain about a dimmer monitor experience, but at least it's consistent once the strobe length is selected. If it were constantly-changing degrees of dimness, that would be even more unpleasant.

What I've just described is a challenge at all refresh rates, not just at low ones.

 

[hawtdawg]

Yes, that much is correct. But even apart from that, with variable refresh you have constantly changing screen refresh intervals. To combine such intervals with strobing, the monitor would need to constantly change the timing of the backlight activation and deactivation. Very complex,

Not really, it could easily be done. It will be done in the future.

and even if you could get it to work, doing so at constantly changing intervals would result in constant variations in perceived monitor brightness. With strobing today, many users complain about a dimmer monitor experience, but at least it's consistent once the strobe length is selected. If it were constantly-changing degrees of dimness, that would be even more unpleasant.
.

how so? you're still looking at a 50% brightness reduction, regardless of the refresh rate.

 

[Black Octagon]

It's not just the power at which the backlight flashes. It's also the amount of time that it stays on, and how long it's been since it last turned off. With variable refresh, these factors are constantly changing, and therefore so too is the perceived brightness.

I am confident the 2 techs will be combined in the future one way or another. But I will be surprised if it's anytime soon, and if the folks on the Blur Busters boards know their stuff, it will certainly not be done "easily"

 

[BFG10K]

how so? you're still looking at a 50% brightness reduction, regardless of the refresh rate.

How did you work that out? Strobing is darker because the backlight no longer has constant persistence.

So if you reduce the backlight frequency even lower (e.g. 40Hz from the usual 144Hz), how could it possibly stay the same brightness?

 

[Dribble]

"Overdrive blur reduction" doesn't exist. It's something you made up. You're confusing the thread by nonsensically mixing terms like that.

The OP isn't missing overdrive; he's missing blur reduction.

Again, repeat after me: overdrive and blur reduction are completely different things.

I guarantee if I grabbed 10 people off the street and showed them something (e.g. live sports) on 2 monitors, one with really fast response time (which is partly achieved via overdrive) and one with a slower response time where you get ghosting occurring because the display can't change fast enough they would all say the slower one is blurry.

It is no different to backlight strobing, it's just another form of blur reduction. If you want to get technical the overdrive is causing the display to switch to the next frame faster, where as backlight strobing is causing your eyes to switch faster (they have 10-20ms of image burn in time). It's essentially working a bit like overdrive, only for your eyes the way to get them to switch frame faster is to show them black. For those that care that's why CRT's are so good - at any one time most of the image is black so your eye sees the current frame, your brain records it, then it sees a lot of black which resets it ready for the next frame.