Thinkpads Forum

Hi, has anyone yet been able to determine the maximum supported external resolution on these? Does the Intel 4500MHD video controller drive 2560x1600 through the ultrabase/displayport option?

Thanks,

P.S. If anyone from Lenovo is reading these - guys, please clean up your documentation. If you're planning to sell so many of these notebooks, please at least bother to hire in some dedicated documentation guy that can do this better than a schoolkid armed with MS Publisher and Frontpage. Check HP's quickspecs or Apple's product pages for good examples of how to do this not-so-incompetently.

The link to tabook is in the sticky at the top of the board.

Looks like single-link DVI-D output from the DisplayPort, which suggests 1920x1200 being the maximum "wide" resolution.

All 2560x1600 30" displays currently require dual-link DVI.

But:
- some new 30" displays use displayport directly (e.g. Dell)
- It is not clear whether or not the docks still support dual-link DVI - the only thing I've seen is that the adapter cable is single link.

Thanks for the responses guys. The tabook document gives more detail - it seems like 2050x1500 or so, i.e. no 2560x1600 30", which is a shame. A X200 with large HDD and full speed components would've made a great docking only-computer.

It seems like the smallest computer one can buy that drives a 30" display is still their T61p/W400 14" line.

Just glanced over the W500 specs, this lists the graphics as Radeon 3650 with no capability to drive a 2560x1600 display. I'm almost certain this is incorrect - the W500 is supposed to be a workstation card (FireGL etc) and these almost always drive 2560x1600.

Lenovo really need to get their sh*t together in regards to documentation, this is awful and makes no sense. Makes me want to switch entirely over to Apple.

This is frustrating for me as well. I'm thinking about the x200 vs picking up a pretty cheap (after current discounts) x61. I have a Dell 30" at home with the dual-link dvi connection (and no other inputs), and being able to drive it is a big factor in the decision. I can't figure it out, but I think I need two things:

1. confirmation that the displayport on the x200 dock will actually drive 2560x1600

2. an active converter from displayport -> dual-link DVI.

I haven't been able to find #2 for purchase, although people say it can theoretically be made.

Anyone else have more information? Am I missing something?

I have reviewed Intel's specs on the graphics chip in some detail and it is ambiguous. The display-port should be able to drive a 30" display - but some OEM support is required. We will need to wait for confirmation from Lenovo or for someone to try it.

awolfe63 wrote:I have reviewed Intel's specs on the graphics chip in some detail and it is ambiguous. The display-port should be able to drive a 30" display - but some OEM support is required. We will need to wait for confirmation from Lenovo or for someone to try it.

I am not an engineer so I do disclaim any errors in my post (which there may be plenty of).

After reading up on the DisplayPort specification from VESA and the Intel GM45 Express chipset technical documentation, the Intel GM45 Express chipset definitely has the capability to run 2560x1600 and beyond.

The Intel GM45 Express chipset specifically supports 4-lane DisplayPort connections at 2.7 Gbps each, giving it a maximum bandwidth of 1080 Mbytes of effective transfer rate (see table below from the VESA spec).

Link rate = 2.7 Gbps
1 lane = 270 Mbytes per second
2 lanes = 540 Mbytes per second
4 lanes = 1080 Mbytes per second

Link rate = 1.62 Gbps
1 lane = 162 Mbytes per second
2 lanes = 324 Mbytes per second
4 lanes = 648 Mbytes per second

(note that the VESA spec seems to imply that they use 10 bits = 1 byte and also that 1 Gbyte = 1 000 Mbyte = 1 000 000 Kbyte = 10 000 000 bits)

The tabook specifies that the maximum external display resolution is 2048x1536@75Hz.

Assuming that the tabook is quoting the maximum resolution supported on the DisplayPort, the following bandwidth requirements should apply (at 24 color bit depth):

(2048 x 1536 x 24 x 75) / (10 x 1000 x 1000) = 566 Mbyte

Assuming that I have not bungled up the calculations or other errors, the above suggests that the maximum supported resolution as quoted by the tabook (and at 24 bits color depth) has such high bandwidth requirements, that it would require a DisplayPort connection running all 4 lanes. The question is then if the X200 hardware is using the 1.62 Gbps or 2.7 Gbps lane speed for communications.

2560x1600@60Hz with 24bits color depth is not possible at 1.62 Gbps.

2560x1600@60Hz with 24 bits color depth is possible at 2.7 Gbps, barring other electronics/components in the X200 or the dock being the limiting factor.

Right. 1.62GHz is clearly supported. That's how DVI works with a cheap adapter. The question is whether the BIOS/driver can detect a 30" monitor and switch to 2.7GHz.

Guys, I found this on the IBM website;

http://www-01.ibm.com/common/ssi/cgi-bi ... anguage=en

I too am think about getting a X200 with the dock, and have a 22" Samsung 2253bw, and wondering what is the max resolution I can display.

That is a 1680x1050 monitor. It will display 1680x1050 - either via VGA or a DisplayPort-DVI adapter.

still haven't found an answer to this one. currently looking at dell's new precision notebooks, both 14/15" models dock to 2 dual-link DVIs/DisplayPorts.

I've now given up as far as their 14" and larger models are concerned, lack of information (this) and progress (15" 1440x900+ models not using LED or keyboard backlighting, last-generation-identical design) are main reasons.

Folks, it will NOT drive a 30" display... see page 124 of the tabook in the right column ("supports single-link DVI-D")

So it'll drive a 1920x1200 24" display fine. It will not drive a 30" dual-link DVI display.

It is not clear if this is because Lenovo has not released the adapter yet or if it is a limitation of the hardware. The graphics chip has the ability to drive a dual-link display through DisplayPort with an adapter as per the DisplayPort spec or a 30" DisplayPort monitor. This requires BIOS support. I have not seen anyone who can reliably say whether these models have such support as of now.

Has anyone had a chance to try this yet? And does anyone know where I can purchase a DisplayPort -> Dual Link DVI adapter/cable? As mentioned above, I have a 3007WFP that only has a dual-link DVI input. Would like to get an x200s if it will drive the monitor... But I haven't even located a cable that will work yet.

So it looks like Apple has a mini Displayport -> dual link DVI adapter here:

http://store.apple.com/us/product/MB571

But to use it with a Thinkpad, I'd have to get a mini Displayport -> normal displayport adapter. Hm. And it is $100.

It is looking like I should just sell my 30" monitor and get something smaller that will easily work with just an inexpensive standard non dual-link cable.

Even if I did keep it, I'm unclear on whether the x200 will drive 2560x1600. Has anyone actually tried it?

jeffbl wrote:So it looks like Apple has a mini Displayport -> dual link DVI adapter here:

http://store.apple.com/us/product/MB571

But to use it with a Thinkpad, I'd have to get a mini Displayport -> normal displayport adapter. Hm. And it is $100.

It is looking like I should just sell my 30" monitor and get something smaller that will easily work with just an inexpensive standard non dual-link cable.

Even if I did keep it, I'm unclear on whether the x200 will drive 2560x1600. Has anyone actually tried it?

I remember that someone in this forum posted that he was able to drive a 2560x1600 monitor with Displayport input, using his new Montevina Thinkpad.

I wonder if this 2048 x 1536 x 75 Hz specification has got any significance at all? Do you know one single monitor that uses 2048 x 1536 natively? Let alone 75 Hz, which seems to be a relict from the CRT age.

I'm also very interested in actual DisplayPort tests. I'd like to combine an X301 and a Dell 3008WFP.

Only CRTs use 2048x1536, AFAIK.

Perhaps that 2048 x 1536 x 75 Hz limit is actually valid for the analog (VGA) port?

Yes. That is the normal limit for a VGA port. VGA doesn't handle 2560x1600.

I'm wondering if I can use the display port AND VGA port on the ultrabase to drive 2 external monitors. I saw this go unanswered in another thread.

I don't expect this to be possible, but haven't seen it confirmed or answered anywhere. I would really appreciate it if someone can clarify.

thanks!

armani007 wrote:I'm wondering if I can use the display port AND VGA port on the ultrabase to drive 2 external monitors. I saw this go unanswered in another thread.

I don't expect this to be possible, but haven't seen it confirmed or answered anywhere. I would really appreciate it if someone can clarify.

thanks!

In general - thinkpads allow this as long as the internal LCD is turned off. I believe all the 4500-based machines work this way.

Hi all. Sorry to resurrect an old thread, but has anyone actually tried driving a 30" monitor at 2560x1600 using an x200 through the dock? It looks like the Apple adapter for mini displayport -> Dual link DVI only works with Apple monitors, so that isn't an option, and I can't find any other adapters that do dual-link. Anyway, has anyone actually tried a direct displayport connection?

I haven't tried that ... but the highest resolutions the Intel driver supports for external monitors are 2048x1536 and 1920x1200. You would need to use a third-party driver, assuming one is available, and assuming the hardware is capable.

Thanks for the response - I guess that clinches it that it will not work! Bummer.

I'm late to the party, but I can confirm that 2560x1600 does indeed work for my X200s w/dock thru a direct DisplayPort cable to a 30" 3008 Dell monitor. The VGA port is also still available, currently driving a 24" Dell at 1920x1200. That's an awful amount of pixels pushed by such a small device...

BTW I found Windows 7 to be better at auto-detecting screens, works like a charm with this set-up.

Wow - that is good news. I see this adapter, but from the listed resolutions, it seems it is not really dual-link DVI:

http://siig.com/ViewProduct.aspx?pn=CB-DP0072-S1

Anyone know of a non-apple dual-link DVI <-> Displayport adapter? Would still love to make this work, and now I have some hope.

jeffbl wrote:Anyone know of a non-apple dual-link DVI <-> Displayport adapter? Would still love to make this work, and now I have some hope.

Yeah although I have it working now, I would still be interested to get a DisplayPort to Dual-Link DVI cable, as I can then use a KVM DVI switch to quickly toggle between computers.
It would need to be an active cable though, so you're probably looking at a price similar to the apple product. I find it strange that Lenovo does not provide one.