I’m not sure how many people occasionally stop to notice this sort of thing, but to me it frequently seems that technology regresses for long periods from it’s infrequent peaks. In the 60s we saw flights of the likes of XB-70 Valkyrie and the SR-71 Blackbird, and people walked on the moon. Yet in 2011 we are reading about the last flight of the Space Shuttle rather than about the first colony on Mars. It makes a quote from Idiocracy all the more uncanny: “… sadly the world’s greatest minds and resources where focused on conquering hair loss and prolonging erections.”
The same pattern seems to apply to some aspects of the computer industry, when cost pressures take precedence over quality, features and innovation. In 2001, we saw the introduction of the IBM T220 monitor, with resolution of 3840×2400 on a 22.2″ panel. It was later superseded by the T221 with very similar specifications, but it was ultimately discontinued in 2005. Nothing matching it has been available since. Today, the screen resolutions seems to be undergoing an erosion. On small panels the “standards” (sub-standards?) have settled at the completely unusable 1024×600, and with total of five exceptions from Dell (3007WFP, 3008WFP, U3011), Samsung (305T) and Apple (Cinema HD), the commonly available screens are limited to 1920×1080 resolution. Even 1920×1200 screens are getting more and more rare, especially on laptops, because screens are marketed by diagonal size and for any given diagonal length, 16:9 ratio screens have a smaller surface area than 16:10 ratio screens.
IBM T221 monitors, especially of the latest DG5 variety, are very hard to come by and still expensive if you can ever find one. Typically they sell for double what you can get a Dell 3007WFP for. But you do get more than twice the pixel count and more than twice the pixel density. I have recently acquired a T221 and if your eyes can handle it (and mine can), the experience is quite amazing – once you get it working properly. Getting it working properly, however, can be quite a painful experience if you want to get the most out of it.
My T221 came with a single LFH-60 -> 2x SL-DVI (single link DVI) cable. There are two LFH-60 connectors on the T221, which allows the screen to be run using 4x SL-DVI inputs. This provides a maximum refresh of 48Hz. There is also a way to run this monitor using 2xDL-DVI inputs at 48Hz, but this requires special adapters, but that is a subject for another article, since I haven’t got any of those yet.
Using a single LFH-60 -> 2x SL-DVI cable, there are only two modes in which the T221 can be run:
1) As a single 3840×2400 panel @ 13Hz using a single SL-DVI port
2) As two separate monitors, each being 1920×2400 @ 20Hz, using two SL-DVI ports
The 13Hz mode is completely straightforward to get working on both RHEL6 and XP x64, but 13Hz is just not fast enough. You can actually see the mouse pointer skipping as you move it, and playing back a video also results in visible frame skipping. So I have spent the effort to get the 2x1920x2400@20Hz mode working on my ATI HD4870X2. The end results are worth it, but the process isn’t entirely straightforward. The important thing to consider is that when running in anything other than 3840×2400@13Hz mode appears to the computer as two completely separate 1920×2400 monitors.
IBM T221 with Linux
ATI‘s Linux drivers aren’t really mature enough for the job, and to achieve the best results, you have to use aticonfig to generate xorg.conf without xinerama support, start X-Windows, fire up the amdcccle configuration utility for ATI cards, enable dual screens, then add xinerama support. If all this sounds complicated to you – it is, and it took a lot of trial and error to get right. So to save you the effort, here is a copy of my xorg.conf file. This is from a RHEL6 machine using the ATI fglrx driver. It will almost certainly work on other distributions, too, with little or no modification.
This still won’t work quite as you’d hope, though – xinerama passes information to the applications about the geometry of the desktop, and apps will only maximize to one screen. This also goes for the task bar, and applies to video playback. The last bit of magic involves faking the xinerama information. Nvidia drivers come with a built in option for this: “NoTwinViewXineramaInfo”. Unfortunately, ATI drivers have no such option. But, this being the world of Linux, there is a backup plan. There is a LD_PRELOAD library called Fake Xinerama that can be used to override the screen geometry passed to applications, and make the applications think they are on a single 3840×2400 screen. All you need to do is the following:
1) Compile fake xinerama from the like above
2) Add the line “/usr/local/lib64/libXinerama.so” to your /etc/ld.so.preload file.
3) Create a file ~/.fakexinerama containing:
1
0 0 3840 2400
The first line contains the number of screens, the second line’s format is:
<origin X> <origin Y> <width X> <width Y>
If you are booting into graphical environment immediately (runlevel 5), you will need the .fakexinerama file in root’s home directory, too, since gdm/kdm run as root.
And if you have managed to follow all that, you will have a single seamless 3840×2400@20Hz desktop.
Do you have any idea where to get that DL DVI-LFH60 special adapter?
As far as I am aware, you can only get them with the monitor, and only if you buy it from this ebay shop:
http://stores.ebay.com/pletisjp
They are not available separately.
Personally, I find 3840×2400@20Hz to be perfectly acceptable even for gaming, just make sure you have vsync enabled. But if you haven’t got the monitor already, it’s certainly worth getting one with the adapter from the shop linked above.
The adapters are readily available in China for about ten bucks. Matrox also sells a short version (about 2′ length cable), not as nice as the IBM but available. They were used with some graphics cards for double-headed displays.
A small correction to your statement about two dual-link dvi connections : no. The dg-5 with the converter box uses ONE dual-link connection plus ONE single-link connection to split the signal in some odd IBM-ish way. The conversion boxes are rare, I’ve never seen one for sale separately from a monitor. It’s probably easier to run four single-link DVI connections to get full resolution at full refresh, if that’s what you need. The earlier version dg-3 runs at 41 hz max refresh and is a bunch cheaper. To be honest, for graphics work that’s probably fine.
Cool that you are using the T221. I also have one and like it. Nice monitor (but shhhh ! don’t tell anyone or you’ll drive the prices up !)
Can you provide a link where the adapters can be purchased on their own?
The adapters in question have two dual link ports – the screen is split into two equal halves, each driven by a dual link DVI cable. Each half runs 1920×2400@48Hz. I don’t think you’d be able to do that mode via a single link on either side.
I found that even 23Hz refresh is fine even for gaming – 23Hz with vsync enabled actually means the frame rates are kept very stable, which help create the perception of smoothness since human eyes cannot actually pick out that many separate frames – higher refresh rates are there purely to remove the appearance of flicker.
I’m sorry … IBM calls the cable an adapter so that’s what I meant — LH60 to two DVI connectors. Those are readily available in China on the Internet and I am pretty sure Matrox sells them in the US.
The converter box is a different deal. It ONLY works with the DG-5 and the way it was intended to work was one dual-link dvi connection plus one single-link dvi draws the full screen at 48hz refresh. IBM-style, they made it slightly strange so one portion of the dual-link drives the odd pixels while another link writes the even ones of 2/3 of the screen, then your single link connection drives the remaining portion. Possibly that was because the graphics cards of the time only had three channels ? People have used two converters with two dual-link connections to drive the monitor but all it does is throw away one portion of one dual-link connection. At some ungodly amount of money per converster box, that didn’t seem like a good idea to me.
Personally, I’m not interested in the converter boxes since four single link dvi connections is simpler and easier to deal with. Out of curiosity, you are running this on Linux ?
I am talking about neither the DG5 “converter box” nor the 2xDVI->1xLH60 cables. I am talking about an aftermarket adapter that takes 2xDL-DVI and plugs into 2xLFH60 connectors on the T221 monitor. This aftermarket adapter produces 2 vertical strips of 1920×2400@48Hz, and requires two DL-DVI inputs.
If you read through my other articles on the subject of the T221 monitor, you will see that I am using it on both Linux and Windows, and have done so with both ATI and Nvidia GPUs.
Are you talking about this:
http://www.2cpu.co.kr/bbs/board.php?bo_table=hardware_2011&wr_id=1195
?
There was a Japanese guy, who recently tried to sell a T221 with such a converter on ebay: http://www.ebay.com/itm/290679589847.
If anybody has an idea, how to get hands on this converter gadget, let me|us know.
Best, Markus
BTW: you get around 34Hz with the usual two DVI-SL connects by reducing unnecessarily long sync gaps. That’s ok for most purposes. A single DVI-SL with 13..17Hz is also usable for most, but confessedly a bit slow.
Best, Markus
2x SL-DVI will only get you 23Hz, IIRC, which is fine – even with gaming and watching videos, the appearance is smooth and seamless. Human eyes can only perceive < 20 distinct images/second. The only reason why high frame rates are traditionally used on monitors is because back in the day CRTs were inherently flickery due to the nature of their functioning.
In fact, gaming can appear smoother when you run at 23Hz because your GPU is more likely to keep up and fill every one of those frames. What you notice as frame skipping is the difference in the delay between the frames, because consecutive frames could differ in complexity. Lowering the screen refresh rate prevents that problem from occurring by evening out the delay between the frames. High refresh rates are something that the GPU vendors have sold to the gamers as being important when it doesn't actually affect the experience even with the best human eyes once you get past about 25 fps. If your GPU is underpowered, try hacking your monitor config to run at 30Hz instead of 60Hz and you'll see that suddenly gaming feels a lot smoother.
1x SL-DVI gives you 13Hz which is too low – you can actually see the mouse pointer skipping around, and gaming and videos are quite obviously skippy.
I know this is a very old thread – I have purchased two of these monitors and am desperatly looking for the correct cable to buy but cannot find it anywhere
DL-DVI to LFH-60
There is no such thing as a DL-DVI->LFH-60 “cable”. If you want to do that you need a special adapter that has 2xDL-DVI plugs and 2x LFH-60 plugs. Those adapters are strictly aftermarket and are specific to the late T221 monitors. It is very rare that those are available separately and when they do turn up on ebay, they are not cheap. It is the price you pay, I guess, for using the best monitor ever made. Let’s face it these aren’t used by anyone who is on a budget.
In the absence of those, you can use two 2xSL-DVI->1xLFH-60 cables (fairly standard, IIRC some Matrox cards shipped with them) – the monitor will appear to the computer as 4x 1920×1200 panels (instead of 2x 1920×2400 panels that the adapter emulates).
Many thanks for your super quick response, any idea where I can order these:
2xSL-DVI->1xLFH-60 cables
Nothing on ebay with that description, could I use the following:
http://www.amazon.co.uk/Matrox-Dual-DVI-Cable-Display/dp/B000I0QIP8/ref=sr_1_9?s=electronics&ie=UTF8&qid=1336573909&sr=1-9
Hmm… I don’t have the T221 in front of me right now so I am not 100% sure of the gender of the connectors on the monitor, but I think this might work. I cannot say for sure without knowing the pin-out, though. Didn’t your monitors come with at least one such cable each?
My monitors that I inherited came with nothin apart from the massive chunky power supply – I just wanted to test them so I can sell further as these are too bulky for me and I do not need a massive resolution.
Because I have no cable I dont want to buy the incorrect one, I think I have searched every thread for a cable or adaptor but to no avail, please please if you know of anywhere where Ican purchase the correct cable from let me know.
I have tried a 60 pin to dual dvi http://www.amazon.co.uk/HP-Video-splitter-DVI-I-PIN/dp/B000225EN4/ref=sr_1_2?ie=UTF8&qid=1336575239&sr=8-2 but this did not work, hence why I dont want to get the wrong cable again.
It’s hard to tell which of these cables are the same and which aren’t, pin-out-wise, without actually checking. I seem to recall hearing somebody mention that the cable for Matrox cards works, but I never tried it myself.
Note that you should be able to get it working with just a single SL-DVI plug of the cable plugged in – plugging in the 2nd DVI plug is purely optional. With a single DVI plug you will get 3840×2400@13Hz (assuming the cable has the correct pin-out and that your monitor is working).
I think this will only work with a male to male cable 60 pin to DVI
Sorry about my ignorance, what is a SL-DVI cable, is it just a standard DVI cable as the monitor definitly requires a 60 pin
Single Link DVI. See here for more details on the subject.
The connectors on the monitor side aren’t DVI, they are LFH-60.