Yamakasi Catleap 27" 100mhz IPS

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The software will try and run it 100Hz but the hardware will not allow it so will drop it back until it can be transmitted.

From what I have read and understand once the card hits it's bandwidth limit depending on the card it will just either hit a huge signal delay or the card will limit the frequency automatically. So even if you are telling it to try and output 100hz @ 2560x1440 it is more than likely not.

You unfortunately cannot beat the limits of the transmission system.

Well done Moogley, that's a lot of researching :D So it seems to be a lot of placebo affects for the people who buy the 100hz Korean monitors. And, if I am reading you correctly, it also means the monitor is running some kind of interpolation, which would introduce a load of input lag.

So gaming would probably be better on the 60hz models. Or have I got this all wrong?

Basically if you test the refresh rate to the real hz your monitor is running at it will show that it is running at 75hz? Or if it shows, for example, a 100hz, then this isn't possible so its some kind of interpolation and not real.
 
Basically if you test the refresh rate to the real hz your monitor is running at it will show that it is running at 75hz? Or if it shows, for example, a 100hz, then this isn't possible so its some kind of interpolation and not real.

I don't think anything really been proven about this, I mean what is doing the interpolation as there is no scalar in the monitors so anything would have to be done on the graphic card.

Best place to ask is on 120hz.net where most of the guys that know more of the technical side of things. I mean why wouldn't it just display the usual out of range error that monitors normally show when they hit an incorrect hz?
 
I don't think anything really been proven about this, I mean what is doing the interpolation as there is no scalar in the monitors so anything would have to be done on the graphic card.

Best place to ask is on 120hz.net where most of the guys that know more of the technical side of things. I mean why wouldn't it just display the usual out of range error that monitors normally show when they hit an incorrect hz?

Well, just looking at the 2B board picture that you supplied, maybe those boards are from a passive 3d display or something and those extra bits on the 2B board are some kind of buffers that store the information for each part of the picture and the dual connection from the board to the PCB are where/when the interpolation happens.

Or maybe it's like Moogley says and the card and monitor are talking to each other and the 2B pcb has a bit more logic and can transmit the frequency range it can support.??

Or maybe the dual link dvi is capable of transmitting the signal but it's running way out of spec and that's why so many people are having problems with the supplied cable.


I don't know, I am only guessing. Moogleys figures seem correct and you can't transmit more than the cable can support, so something extra is happening.
 
If you read up on how dvi works especially dual link it is pretty clear that exceeding the bandwidth limitations is pretty much impossible. Also the cards max 400hz clock is a huge limiting factor.

I'm not claiming to be an expert or anything I'm just interested how it all works and have had a read through tons of info.what I have learnt is don't trust what your software is telling you as the hardware will override it no matter what.

You must ask why is there no 120hz 1440p screens either IPs or tn and it seems the limiting factor is the data transmission system used with dvi. Until display port v1.2 is the common connection or dvi is re-vamped to handle the bandwidth its just not going to happen.

Unless it already has I might be wrong I usually am so do your own research and prove me wrong cause Tbh I would love a 120hz 1440p IPs screen....:D
 
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Even if the technical limitations of 'insufficent bandwidth' were overcome you would still have insufficiently rapid pixel responses to overcome. Remember that LG don't produce 120Hz IPS models that are 23" (1080p) or 24", either. If they did they wouldn't be able to make use of 120Hz technology for exceptional fluidity in the same way that TN panels can. These Korean monitors don't even feature proper pixel overdrive so they are not good candidates for 120Hz technology regardless of bandwidth.
 
Here is what NCX says about the overdrive on the Korean monitors

"I keep reading about people saying these Korean models lack overdrive which seems to confuse or deter some potential buyers. This simply is not true

Of course they are over driven, other wise they would not be able to achieve such low measured response times. See this chart:

http://down.playwares.com/xe/files/a...6c55a13abc.jpg

The Crossover is faster than many TN panels....how could it be if it lacked overdrive?

Having used the 27Q LED-P and seeing it overshoot (bright glow/shield or halo forming around moving objects) only confirms that they are actually over driven a little too much. If they lacked overdrive there would be very noticeable colour smearing even with very slow camera movement, smearing like you would find on some of the older C-PVA panels and the measured response times would not be so low."
 
If you read up on how dvi works especially dual link it is pretty clear that exceeding the bandwidth limitations is pretty much impossible. Also the cards max 400hz clock is a huge limiting factor.

I'm not claiming to be an expert or anything I'm just interested how it all works and have had a read through tons of info.what I have learnt is don't trust what your software is telling you as the hardware will override it no matter what.

You must ask why is there no 120hz 1440p screens either IPs or tn and it seems the limiting factor is the data transmission system used with dvi. Until display port v1.2 is the common connection or dvi is re-vamped to handle the bandwidth its just not going to happen.

Unless it already has I might be wrong I usually am so do your own research and prove me wrong cause Tbh I would love a 120hz 1440p IPs screen....:D

Well, according to some people on other forums, Phunky is right and there is no bandwidth limit to dual link DVI. Which makes no sense to me. You have a cable with 12 pins that can do 4Gbits max now if you increase the number of pins by 12 to 24 you suddenly have a cable that has unlimited bandwidth!!

Isn't science brilliant :D
 
Well I was just going on the majority opinion there. I haven't used one of the monitors myself and a colleague of mine from Hong Kong who likened the performance to the ACD which does lack overdrive (some seem to lack overdrive though so maybe this is why). Going from the numbers and the experience of NCX (I don't doubt he knows overdrive when he sees it) then it is fair to say they do have overdrive. Even so the comments above regarding 120Hz being of limited attractiveness on these monitors still stands. For people who like to go by the numbers remember that some of the better 120Hz TN panel monitors typically achieve 2-3ms grey to grey (measured correctly by websites like Prad.de) and these Korean monitors are roughly a third as fast. It goes without saying that the technology isn't ripe for 120Hz like TN panel technology is and that is one of the reasons LG hasn't really pushed for this (same with Samsung and their PLS technology). There would still be some benefit to be gained by a properly supported 120Hz refresh rate on an IPS panel monitor I'm sure. I am hoping we will see 120Hz VA panels later this year - certainly not the most likely candidate for 120Hz technologies. It could be primarily to facilitate active 3D technologies as it was for TN panel monitors originally - and that is another reason LG isn't pushing as their passive 3D technology works just fine at 60Hz.
 
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The software will try and run it 100Hz but the hardware will not allow it so will drop it back until it can be transmitted.

From what I have read and understand once the card hits it's bandwidth limit depending on the card it will just either hit a huge signal delay or the card will limit the frequency automatically. So even if you are telling it to try and output 100hz @ 2560x1440 it is more than likely not.

You unfortunately cannot beat the limits of the transmission system.

Well apparently you can beat the limits of the transmission system, It's magic!! :D
 
looking at _korea he has 2 shimian listed and ones an ipsb can anyone tell me the difference between the 2 as they're very similarly priced, yes I'm getting very close to buying lol like the crossover but not sure its worth the extra 40 quid or so.

any help appreciated
 
I here allot of people arguing about the bandwidth limitations of Dual L DVI....

Dual L DVI has a certain Bandwidth it is tested at to pass as a fully functional DL DVI.

The same as HDMI 1.4 or HDMI 1.3

But this doesn't mean that a good quality DL DVI cable cant produce a 100hz signal on a 1440p image, just like one HDMI 1.3 cable can potentially be used instead of a HDMI 1.4 cable it just isnt tested and passed as the 1.4 certification.

If you have a good quality Dual Link DVI you have a good chance it will display 100hz at 1440p, people here are acting as if it hits a brick wall at its tested specification, which isn't true, nearly all can handle more bandwidth than the DL DVI specification,just depends on the quality of the cable how much more, its just they are not tested for it.
 
The difference in bandwidth is immense. There is simply not enough available to be able to transmit the signal. The cable is only a small part you also need to consider the transmission system and the current max clock of the card.
Trying to push 15.75 Gbit down a system that can at max take 9.9 Gbit is just not going to end well. Cable quality is a very small factor as the biggest problem is you just don't have the available bandwidth. A poor quality cable is likely to cause Jitter but this has little effect on bandwidth.
 
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This should explain my theory and reasoning a little better in short you cannot output anything over 2560x1440 @ a max of 75hz using a dual link dvi transmission system..

You should be well aware of the fact that transmitting stereoscopic 3D content over a video interface requires more bandwidth and depending on the interface and the type of 3D content the required bandwidth is usually twice more, or a bit less, than that needed for sending 2D content. I’m talking about sending uncompressed images for both left and right eyes of course as there are some solutions that use compression to save bandwidth, as using compression might increase the price and complexity of the product and add some delays, but this however is something that is not good to have when talking about 3D displays. And here I’m going to be talking about what is the possible near future of 3D displays and more specifically 3D monitors intended for use with computers…

Currently all more recent 120Hz 3D monitors use Dual-Link DVI as an interface for transferring stereoscopic 3D data from the computer to the display using frame-sequential mode. These are of course LCD monitors using faster panels that can work with 120Hz refresh rate, so with a pair of active shutter glasses you are able to split the sequence of images being displayed into a left/right pairs and thus allow the user to see 3D with 60 frames per eye. The alternative is to use a 3D display with passive polarization in order to save bandwidth, but then you will also have some loss of resolution and thus you loose a bit of the quality in 3D mode and that is considered as a somewhat of a compromise and we don’t want to compromise with quality when talking about stereo 3D, right? Anyway, having a display working with 120Hz refresh rate at Full HD resolution of 1920×1080 pixels requires a lot of bandwidth and it pretty much fills in the capacity provided by the DL DVI interface (note it is Dual and not Single Link DVI). This is of course the current state of things with active shutter solutions, but what will happen in a few years when displays with higher resolutions start to appear and users would want to have faster refresh rate even in 3D mode? Obviously the Dual-Link DVI interface will not be able to do that job, so we’ll need another interface and we actually have that interface available for quite some time, it is called DisplayPort. An interface that can provide higher bandwidth and offer more for 3D-capable solutions, not to mention that it is royalty-free, unlike the HDMI interface where you have to pay for each device equipped with the interface as well an yearly fee to use the interface.

Mentioning the HDMI interface, I should go on a bit about it and especially regarding the HDMI 1.4 specification of the interface that was released in 2009 and later on updated to 1.4a in 2010. The HDMI version 1.4 specifications of the interface have introduced official stereoscopic 3D support and since then this has become the defacto standard for ensuring 3D compatibility and interoperability for 3D-capable consumer electronic devices. All of the recent 3D HDTVs, Blu-ray 3D players and so on use HDMI 1.4 interface and you can pretty much guess that none of them has a DVI interface, or a DisplayPort for that matter. HDMI is an interface developed and designed for and by the consumer electronics industry and while it is also going quite strong in the IT industry it is not going to replace more typical computer interfaces for video such as DVI. The computer industry’s counterpart for the HDMI interface is the DisplayPort, but unfortunately DisplayPort is still not that well developed and as commonly used as DVI or HDMI and that is still causing delays with the adoption. The major problem with the HDMI 1.4(a) interface is that it is more bandwidth limited and you cannot even have 1080p resolution in stereo 3D mode with more than 24Hz (24 frames per eye), a resolution/refresh rate combination that is ideal for 3D movies, but not that good for stereo 3D gaming. But since the development of the stereo 3D specs of this interface had to take into account the requirements of consumer electronics devices such as game consoles and Blu-ray players it has been decided that defining 720p 50/60Hz 3D mode and 1080p 24Hz 3D mode was enough. The PC has been completely left outside of the equation, so that Dual-Link DVI was the solution adopted for 3D monitors intended to be used with computers in order to provide up to 1920×1080 resolution at 120Hz (actually DL-DVI can support 1920×1200 @ 120Hz as well, but there are apparently no 120Hz panels to support that resolution).

Let us get back to the DislayPort interface as this is considered to be the new interface for 3D-capable monitors as it can even now provide much more than what HDMI and Dual-Link DVI interfaces are capable of in terms of bandwidth. DL-DVI is enough for the current generation of 3D monitors, but there are already people looking for 2560×1600 resolution and 120Hz refresh or asking about 120Hz refresh rate per eye in 3D mode and not only in 2D on Full HD displays. Such requirements are not possible unless DisplayPort is used and more specifically DisplayPort version 1.2 that has been approved in 2009, because earlier revisions of the interface are a bit more limited in terms of stereo 3D support. The truth is that DisplayPort was 3D-capable interface even back in 2007 when version 1.1a of the standard has been approved, but back then it was still way too new (the first version of the interface was approved in 2006). DisplayPort 1.1a had support for frame sequential stereo and could provide 1080p resolution with 60Hz per eye in 3D mode, but due to limited support of the interface on video cards back then DL-DVI was the preferred choice. Now the newer DisplayPort 1.2 has even better support for stereoscopic 3D displays and can provide up to 120Hz refresh rate per eye in 1080p resolution or 2560×1600 with 60Hz per eye in 3D mode. The 1.2 version of the interface supports not only frame sequential format, but can also work with Side by Side, Top/Bottom, Line and Pixel interleaved modes. There is also an enhancement of the EDID allowing display manufacturers to describe what is their 3D monitor using DisplayPort is capable of supporting in 3D mode, so that the capabilities of the display can be automatically read by the computer software.

If you are already wondering why in the hell there are no 3D monitors on the market that take advantage of all the extra capabilities that the DisplayPort 1.2 interface is offering there is a simple answer. The DisplayPort interface is still not that common enough and available on all more recent video cards sold in the last 2-3 years, so display manufacturers are still mostly adding that interface on higher-end products as an extra feature, but it is not yet considered to be of major importance. For example most of the latest video cards based on Nvidia GPUs still don’t come with DisplayPort on them as a standard feature, the situation with more recent AMD-based video cards is better as they all come with at least one DisplayPort interface on the backplane. But it is not only up to hardware, the software also needs to support stereo 3D over DisplayPort and the situation there is still not that good as well. AMD just recently introduced official support for stereo 3D over DisplayPort in their latest Catalyst Software Suite Version 11.9 that has been released a few days ago (there was beta support in an earlier preview driver, but users had problems making it work). But this support comes along after the recent release of the first 3D monitors equipped with DisplayPort interface and these are the Samsung 750 and 950 series of 3D-capable displays. Nvidia is a bit late on introducing stereo 3D support over DisplayPort interface, but there are also no 3D-capable monitors compatible with their 3D Vision technology being announced yet, so they are probably not in a hurry to do that like was in the case with AMD (the products were already on the market). But if you want a 240Hz Full HD LCD monitor or a 2560×1600 120Hz one you would still have to wait a bit more for software and for hardware to catch up with the specifics and requirements needed to support these as DisplayPort is just one of the things needed that is already available, but there are other requirements that still need to be fulfilled. I mean things such as faster response LCD panels as with the current generation of 120Hz TN panels we are still having issues with crosstalk/ghosting. Having a video card (you’d need multiple) that can push 240 fps in Full HD resolution or 120 fps in resolutions higher than Full HD also isn’t an easy thing and here is no point in having a 240Hz LCD monitor if you cannot feed it with even 120 fps. And even at the moment top GPUs are having problems pushing constant fps of around 120 in more demanding games, so don’t be in a hurry with super big requirements for your next 3D monitor. Still in the next few years if the user interest in 3D technology keeps rising, there is much more content available and the prices continue to get more and more affordable thing might move in the right direction and DisplayPort can finally find the place it deserves, but we’ll have to wait and see…
 
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This is true, its not just about the cable.

I am just putting to bed the people on here naively thinking that cables can only produce a certain amount of bandwidth.
When in reality no, thats the least amount of bandwidth they can handle and what they are tested at (unless very cheap and poor quality). And any good quality cable will always handle more than that, sometimes allot more.

In short, if you don't know what you talking about. Don't go and search in google the bandwidth of a cable and come back arguing that "this is all it can do" when you are wrong, thats the least it can do. There's no argument about whether the cable can handle the bandwidth, its the limitations of the system as pointed out above, and if you don't know anything about that, then you may as well not argue and bring up irrelevant things you have found in good and miss-interpreted for the sake of an argument you know nothing about.
 
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In short, if you don't know what you talking about. Don't go and search in google the bandwidth of a cable and come back arguing that "this is all it can do" when you are wrong, thats the least it can do. There's no argument about whether the cable can handle the bandwidth, its the limitations of the system as pointed out above, and if you don't know anything about that, then you may as well not argue and bring up irrelevant things you have found in good and miss-interpreted for the sake of an argument you know nothing about.

Why are you get a hard on here ? The dual link dvi system cannot handle the bandwidth the cable is irrelevant. When have I mentioned the cable ?

The bandwidth limits are on the transmission systems used in dual link Dvi there is a lot more to dual link Dvi than just a cable which I have tried to explain.

I have an understanding of digital transmission systems and was just trying to work out using the information available how/if you could send a 2560x1440 120hz signal down a dual link dvi. Surely if people cannot search for information then how do people learn and improve their knowledge ?

Please refrain from posting insults and maybe do some re-search yourself and post some good gen on the problem.
 
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Why are you get a hard on here ? The dual link dvi system cannot handle the bandwidth the cable is irrelevant. When have I mentioned the cable ?

The bandwidth limits are on the transmission systems used in dual link Dvi there is a lot more to dual link Dvi than just a cable which I have tried to explain.

I have an understanding of digital transmission systems and was just trying to work out using the information available how/if you could send a 2560x1440 120hz signal down a dual link dvi. Surely if people cannot search for information then how do people learn and improve their knowledge ?

Please refrain from posting insults and maybe do some re-search yourself and post some good gen on the problem.

Im not talking to you, there have been numerous posts arguing about the DL DVI cable not having enough bandwidth and only having a max of 9.9gb/s which is wrong, that's the least they have.

And that's the point which you have clearly pointed out, the cable is irrelevant and not the limitation, its the system itself, so these people are arguing about the cable when all they have done is searched what badwidth a DL DVI is tested at then based there argument on that not knowing what they are talking about otherwise they would know thats not the limitation.

I have posted no insults, just set the record straight, nothing to do with you and don't know why you think that so dont get all offensive and imply I am throwing out insults when Im clearly not.
 
Im not talking to you, there have been numerous posts arguing about the DL DVI cable not having enough bandwidth and only having a max of 9.9gb/s which is wrong, that's the least they have.

And that's the point which you have clearly pointed out, the cable is irrelevant and not the limitation, its the system itself, so these people are arguing about the cable when all they have done is searched what badwidth a DL DVI is tested at then based there argument on that not knowing what they are talking about otherwise they would know thats not the limitation.

I have posted no insults, just set the record straight.

Fair enough I take that back I misinterpreted your post...
 
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