Blur Busters Forums

Who you gonna call? The Blur Busters! For Everything Better Than 60Hz™ Skip to content

Questions/opinions about XB271HU and 27GK750F-B

Everything about displays and monitors. 120Hz, 144Hz, 240Hz, 4K, 1440p, input lag, display shopping, monitor purchase decisions, compare, versus, debate, and more. Questions? Just ask!

Questions/opinions about XB271HU and 27GK750F-B

Postby Kheri » 15 Oct 2018, 20:11

So I've been making an effort to research what I could (I've actually been a reader of blurbusters for a couple years on and off, now.) And I'm looking to buy a good monitor for gaming (not just twitch shooters or competitive games as I don't play that competitively, but it's sort of a foucs.) I'm looking for some opinions, thanks.

I'm looking at a couple monitor options. I play some shooters (and I'd like to be good at them) but I don't play all that competitively or at high levels. I believe I'd really like low motion blur. As I understand it, above 120/144hz there isn't much improvement in 'smoothness' but there is in non-strobed motion blur. Although I think I'd still notice the phantom array effect at times. I can play one to three competitive games I have without dipping below 240fps. The rest I can't (GPU not strong enough.)

The LG 27GK750F-B looked like a good monitor but unfortunately it's a freesync monitor. From what I read, the crosstalk isn't bad but isn't possible to adjust fully. However it's still very good at reducing motion blur and can do so at 240hz. So I'd be running it @ 240hz mbr for a couple games (probably with vsync off, but maybe with low-lag rtss, and in Original Mode). For most other games I'd be running it at either 144hz or 120hz. Is this a good monitor for motion blur reduction?

The Acer Predator XB271HU has some advantages over a 240hz TN. It's 1440p and has better colors because it uses an IPS panel. It's also g-sync and can run ulmb+g-sync hack from what I understand. I believe the ULMB would be dimmer than a 240hz panel at the same MPRT/persistence level. And the ULMB runs at 120hz (can't run higher, I think.) In this case, is it true this monitor would have trouble with ghosting/smearing at 120hz ulmb (should I avoid if so)? The response times seemed decent. Are the IPS colors (and higher res) worth it compared to a good 240hz TN panel if they're both calibrated well? (i.e. is there much difference?)

I was considering a VA panel but I don't want to deal with the ghosting or smearing VA panels suffer from. It would be kinda nice to go below even 1ms MPRT, of course. Are there better monitors I should buy instead? New and better monitors should be coming out within a couple years, no? I hope it's okay for me to post questions here about buying a monitor, apologies if it isn't.
Kheri
 
Posts: 12
Joined: 29 Sep 2018, 13:39

Re: Questions/opinions about XB271HU and 27GK750F-B

Postby RealNC » 15 Oct 2018, 20:33

If you're interested in ULMB, you should probably pick a TN panel. There is some crosstalk in IPS panels, and way too much in VA panels.

One thing to note about colors though: it's not colors per se that are better on IPS and VA. Sure, if you measure them, they are better, but subjectively, they're not too different from TN. They are a bit livelier on IPS, but subjectively, the difference is not something that sticks out, unless you place the monitors right next to each other.

The bigger difference is in general image quality. Gamma, contrast and clarity are better on IPS (and VA.) On TN, it only looks good at the very center of the screen, while away from the center it changes. Level of detail is consistent across the screen on IPS and VA, while on TN it isn't. IPS has angle-dependent glow (and VA also has something similar), which TN doesn't have. So it's kind of a "pick your poison" situation. Personally, I much prefer IPS glow to TN gamma/contrast shift, because IPS glow does not affect level of detail.

A pcmonitors.info has a video showcasing this and talking about on the XG2703-GS review (a 1440p 165Hz G-Sync monitor, I've been using that one for over a year now.)

https://www.youtube.com/watch?v=bYKUFNS ... u.be&t=645
TwitterSteamGitHubStack Overflow

The views and opinions expressed in my posts are my own and do not necessarily reflect the official policy or position of Blur Busters.
User avatar
RealNC
 
Posts: 2077
Joined: 24 Dec 2013, 18:32

Re: Questions/opinions about XB271HU and 27GK750F-B

Postby Kheri » 16 Oct 2018, 00:16

I did not know IPS panels had any more crosstalk than TN. TN has some, right? Or is it at least possible for it to have none?

I think AMD is releasing their new GPUs in some months from now. Would be nice if they made some FreeSync protocol for sync'ing up with backlight strobing / motion blur reduction. I'm not even sure if that's possible. I doubt AMD will, anyway.

Thanks for your opinion and advice. I might go with a good TN panel if I can find one, just a shame to miss out on g-sync and (to a minor extent) better colors. Hopefully I get some more opinions.

The 27GK750F-B doesn't actually have that great of response times, so I'm not sure why the Acer Predator's IPS panel has some trouble with ULMB.
Kheri
 
Posts: 12
Joined: 29 Sep 2018, 13:39

Re: Questions/opinions about XB271HU and 27GK750F-B

Postby RealNC » 16 Oct 2018, 00:34

Kheri wrote:I did not know IPS panels had any more crosstalk than TN. TN has some, right? Or is it at least possible for it to have none?

TN still has some, but IPS has more. And VA even more. There's some upcoming TN panels with a response time of 0.5ms, which should in theory make crosstalk barely visible, but not sure when those come out. (The cause of strobing crosstalk is pixel transition time, so the lower that gets, the less crosstalk there is.)

Thanks for your opinion and advice. I might go with a good TN panel if I can find one, just a shame to miss out on g-sync and (to a minor extent) better colors. Hopefully I get some more opinions.

For what it's worth, I almost exclusively use g-sync instead of ULMB. It's personal preference, but once I get past 100FPS g-sync, motion blur does not bother me anymore. The only use case that's left for me for ULMB is sub-90Hz. I use 85Hz ULMB for example sometimes, and a custom 60Hz ULMB mode too on occasion. But 95% of the time, it's g-sync that brings me the most fun in gaming.

The 27GK750F-B doesn't actually have that great of response times, so I'm not sure why the Acer Predator's IPS panel has some trouble with ULMB.

Pixel response times. It's about 4ms as stated by the manufacturer. Real pixel response is about 5 to 6ms. That's completely fine for non-ULMB (144Hz for example has a frame time of 6.9ms, so the IPS panel used is perfectly adequate for 144FPS non-ULMB.) But when using ULMB, you need pixels to transition in less than 3ms or so. A "1ms" TN panel usually has around 3ms real response time, which is why there's still a bit of crosstalk. The new "0.5ms" panels will probably have 1-2ms of real response, so crosstalk should be almost invisible. (Famous last words.)
TwitterSteamGitHubStack Overflow

The views and opinions expressed in my posts are my own and do not necessarily reflect the official policy or position of Blur Busters.
User avatar
RealNC
 
Posts: 2077
Joined: 24 Dec 2013, 18:32

Re: Questions/opinions about XB271HU and 27GK750F-B

Postby Kheri » 16 Oct 2018, 01:27

RealNC wrote:Pixel response times. It's about 4ms as stated by the manufacturer. Real pixel response is about 5 to 6ms. That's completely fine for non-ULMB (144Hz for example has a frame time of 6.9ms, so the IPS panel used is perfectly adequate for 144FPS non-ULMB.) But when using ULMB, you need pixels to transition in less than 3ms or so. A "1ms" TN panel usually has around 3ms real response time, which is why there's still a bit of crosstalk. The new "0.5ms" panels will probably have 1-2ms of real response, so crosstalk should be almost invisible. (Famous last words.)

Why 3ms?

Looking at TFTcentral, the pixel response/transition times for the LG is 1.1 to 9.7ms (4.2ms average) with Overdrive on normal (2.7ms on maximum overdrive, but im not playing on that.) I'm not sure how exactly the blanking interval works to hide the transitions, and how much time is required. But if you require half a frame to hide the transitions, wouldn't that make the highest refresh rate this panel should be run at with MBR (1ms persistence) 119hz (1000 / (4.2ms * 2))?

The Acer Predator's IPS panel's G2G response is 5.9ms avg on 144hz and 6.3ms on 120hz (don't think, or know if, it can run ULMB at 144hz). so 79hz. ULMB can be set to 1ms persistence I believe, but makes the screen even dimmer. Which was another reason for me to consider a 240hz panel (brighter ulmb/mbr, better ulmb/mbr.) I'm not sure how this works, actually, and need to look into it. I thought it'd be something like, for an 8.3ms frame and 1ms persistence: frame is black for 7.3ms, frame shows for 1ms. Maybe the pixels transition twice, or more backlight time.. etc. I'll have to learn it, but asking here too. The IPS panel's transition is only 2.1ms longer, which makes me wonder how the LG's MBR can be pretty decent operating at 240hz. I'm looking at the TFTcentral backlight cycling graph for the 27GK750F-B and I don't really get how the pixel transitions fit well in the off periods.

Wonder when those new monitors will be released.
Kheri
 
Posts: 12
Joined: 29 Sep 2018, 13:39


Return to General — Displays, Graphics & More

Who is online

Users browsing this forum: ZoRG172 and 11 guests