FAO Baddass/ PCM2 - Can a 3440 x 1440 panel not do more than 75hz???

wunkley

wunkley

wunkley

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In light of the VERY disappointing news in this thread http://forums.overclockers.co.uk/showthread.php?t=18650953 I wanted to ask those more in the know.

Is it currently not technically possible for a 3440 x 1440 panel to be more than 75hz? I seem to recall reading on here that current display port technology should allow for up to 120 or even 144hz at this res, but is not good enough yet for 4k.

Would appreciate some clarification on the technical facts here. I'm going to do a new build in a few months time, with a new screen and I need to know what I'm dealing with, or what's potentially worth waiting for...
 
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There is currently only one 3440 x 1440 IPS panel used (plus a curved variant). After effective (but not excessive) pixel overdrive is applied there are some pixel transitions that are too slow for optimal 60Hz performance, although some which are more than adequate. I feel that pushing these panels much beyond 75Hz would be problematic, they simply aren't fast enough. So it is really that the panels aren't currently available to do this, although I don't doubt that they will be in the future. Especially having seen what AUO's 144Hz AHVA panel is capable of.
 
This is quite disappointing as I was hoping for a 144hz g-sync curved monitor within the next few months, looks like I'll have to stick at the XB270HU! Still, not a bad unit!
 
PCM2 said:
There is currently only one 3440 x 1440 IPS panel used (plus a curved variant). After effective (but not excessive) pixel overdrive is applied there are some pixel transitions that are too slow for optimal 60Hz performance, although some which are more than adequate. I feel that pushing these panels much beyond 75Hz would be problematic, they simply aren't fast enough. So it is really that the panels aren't currently available to do this, although I don't doubt that they will be in the future. Especially having seen what AUO's 144Hz AHVA panel is capable of.
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Hey cheers PCM2 :)

I was assuming they would be totally new panels given the promises of 144hz. Seems like they're not then, at least the IPS ones.

What's the 144hz AHVA panel you're referring to? Is that a 'traditional' VA panel or an ips type with confusing naming?
 
wunkley said:
Hey cheers PCM2 :)

I was assuming they would be totally new panels given the promises of 144hz. Seems like they're not then, at least the IPS ones.

What's the 144hz AHVA panel you're referring to? Is that a 'traditional' VA panel or an ips type with confusing naming?
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another proprietary "IPS-like" panel type that offers similar performance to PLS. Developed by AUO, AHVA is short for Advanced Hyper-Viewing Angle.
Click to expand...
 
wunkley said:
Hey cheers PCM2 :)

What's the 144hz AHVA panel you're referring to? Is that a 'traditional' VA panel or an ips type with confusing naming?
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It's the latter. :p It's the 144Hz 2560 x 1440 'IPS' panel used in the Acer XB270HU and upcoming ASUS MG279Q. :)
 
Ah yes, cheers for that.

So, if 2560x1440 AHVA, basically ips, can do 144hz, can a 3440x1440 variant of the same panel achieve 120hz or even 144hz? Does current display port tech etc allow it, or is it simply not achievable yet and won't be for a while?
 
I've no doubt they'll be able to. I'm doing a New build soon though, and need to know if it's current display port tech etc that's the limit. If it is then we are probably looking at years rather than months I would guess?
My quest for the perfect monitor continues...
 
there's a few considerations to providing 3440 x 1440 at 144Hz. Firstly you need a video interface / video controller which can support sufficient bandwidth to run that res and refresh rate. i'm trying to find a calculation showing the necessary bandwidth for that, and whether that is then supported by current DisplayPort standards. i believe it can be, but not 100% sure.

As PCM2 has eluded to as well, there are considerations when it comes to response times. This is the main limitation really at the moment when providing high refresh rate IPS-type panels. You need response times to be consistently under 6.93ms G2G to be able to reliably offer 144HZ refresh rates. any slower and the response times can't keep up with the frame rate. You get a lot of blurring then, which is the problem the overclocked Korean screens have. Their response times are generally pretty slow (from what i've seen and tested) and they're not really designed to be able to cope with higher refresh rates up to around 100 - 120Hz like some people achieve. Anyway, i digress.

IPS-type panels have been stuck at around 8 - 8.5ms G2G response times at best for a few years (without driving them lower with too much overdrive and leading to massive overshoot problems). AU Optronics have recently managed to push response times of their AHVA (IPS-type) panel used in the Acer XB270HU down to nicely under 6.93ms which has allowed them to finally provide a 2560 x 1440 @ 144Hz IPS-type panel. The other main manufacturers of IPS technology, LG.Display and Samsung (PLS) haven't released any high refresh rate panels yet. LG.Display have a 27" 1920 x 1080 @ 144Hz panel planned for Q3 this year, but given how long it's taking them to get that to market i can only assume they're having a lot of difficulty driving response times down. Samsung don't have any high refresh PLS panels on their roadmap that i've seen yet.

So at the moment AUO have only achieved it on one panel. They don't currently make 34" panels at all, so if a manufacturer wants to produce a 34" IPS screen like this then they only have the small selection available from LG.Display (see here for available panels). So at the moment the limitation is that there aren't any high refresh 34" panels at all. I don't expect we will see any soon either, unless AUO start to invest in that sector and manage to replicate what they've done with their 27" module.
 
Baddass said:
there's a few considerations to providing 3440 x 1440 at 144Hz. Firstly you need a video interface / video controller which can support sufficient bandwidth to run that res and refresh rate. i'm trying to find a calculation showing the necessary bandwidth for that, and whether that is then supported by current DisplayPort standards. i believe it can be, but not 100% sure.

As PCM2 has eluded to as well, there are considerations when it comes to response times. This is the main limitation really at the moment when providing high refresh rate IPS-type panels. You need response times to be consistently under 6.93ms G2G to be able to reliably offer 144HZ refresh rates. any slower and the response times can't keep up with the frame rate. You get a lot of blurring then, which is the problem the overclocked Korean screens have. Their response times are generally pretty slow (from what i've seen and tested) and they're not really designed to be able to cope with higher refresh rates up to around 100 - 120Hz like some people achieve. Anyway, i digress.

IPS-type panels have been stuck at around 8 - 8.5ms G2G response times at best for a few years (without driving them lower with too much overdrive and leading to massive overshoot problems). AU Optronics have recently managed to push response times of their AHVA (IPS-type) panel used in the Acer XB270HU down to nicely under 6.93ms which has allowed them to finally provide a 2560 x 1440 @ 144Hz IPS-type panel. The other main manufacturers of IPS technology, LG.Display and Samsung (PLS) haven't released any high refresh rate panels yet. LG.Display have a 27" 1920 x 1080 @ 144Hz panel planned for Q3 this year, but given how long it's taking them to get that to market i can only assume they're having a lot of difficulty driving response times down. Samsung don't have any high refresh PLS panels on their roadmap that i've seen yet.

So at the moment AUO have only achieved it on one panel. They don't currently make 34" panels at all, so if a manufacturer wants to produce a 34" IPS screen like this then they only have the small selection available from LG.Display (see here for available panels). So at the moment the limitation is that there aren't any high refresh 34" panels at all. I don't expect we will see any soon either, unless AUO start to invest in that sector and manage to replicate what they've done with their 27" module.
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Brilliant reply, thanks very much Baddass, love this forum sometimes :)

I think I will look at sticking with my current Rog Swift for my new gaming build then, and might look at going IPS 4k for my other 'work' comp instead. Not an option I was even considering until now. Hmmmm
 
wunkley said:
In light of the VERY disappointing news in this thread http://forums.overclockers.co.uk/showthread.php?t=18650953 I wanted to ask those more in the know.

Is it currently not technically possible for a 3440 x 1440 panel to be more than 75hz? I seem to recall reading on here that current display port technology should allow for up to 120 or even 144hz at this res, but is not good enough yet for 4k.

Would appreciate some clarification on the technical facts here. I'm going to do a new build in a few months time, with a new screen and I need to know what I'm dealing with, or what's potentially worth waiting for...
Click to expand...

Bare in mind that these current high res/high refresh panels are not an improvement on existing designs but new developed designs in their own right (i.e. they haven't just taken the panel from the XL2420 and bumped it upto 2560x1440) - I'm not sure how true it is but I heard that the 2560x1440 120+Hz TN was almost an accident with the original project not a 120+Hz one but intended as general development of AUO's (part of BenQ group) AHVA tech (the colour reproduction, especially whites have some traits more commonly found on HFFS panels so I'm inclined to somewhat believe it).
 
3440*1440 24bpp @144hz is 17.12 Gbit/s
displayport1.2 has 17.28Gbit/s

by the time you add signalling overhead I dont think it does have enough bandwidth, so it needs to be DP1.3
 
120Hz could be achieved then at 3440 x 1440? 120hz is more than enough. Or is that still pushing the maths too much
 
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:confused: Not following your point. This thread is about "Can a 3440 x 1440 panel not do more than 75hz???" ie is current display port tech and bandwidth issues limiting the possibility of high Hz superwide screens.
 
Baddass said:
of their AHVA (IPS-type) panel used in the Acer XB270HU down to nicely under 6.93ms which has allowed them to finally provide a 2560 x 1440 @ 144Hz IPS-type panel
Click to expand...

Will we see this panel from other brands with G-sync in the upcoming months?
 
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