Thinkpads Forum

I am going to get a x201 with x200 Ultrabay and also DELL SP2309W, which supports 2048x1152 with VGA, DVI & HDMI input. In my understand, DisplayPort on x200 Ultrabay may be converted to DVI through a converter, which supports up to 1920x1200. The resolution is not enough for the monitor. If I get a DP-to-HDMI converter, can I get 2048x1152 output? Thanks.

Ed

I received a Dell sp2309w today and like it very much! For a TN-type LCD panel, this is one of the best I have seen. Some people may not like the glossy surface but I am using this monitor in a darkroom and so reflection won't be a problem.

Why don't you just use the VGA output? If the monitor is set up properly, image quality through VGA is pretty much as good as the other types of input. I just looked up several DisplayPort-to-HDMI and DisplayPort-to-DVI adapters and their maximum resolutions were either 1920x1080 or 1920x1200. 2048x1152 is a little higher than 1920x1200 and thus would probably not work.

pianowizard wrote:Why don't you just use the VGA output? If the monitor is set up properly, image quality through VGA is pretty much as good as the other types of input.

VGA is analog interface, in order for it to work acceptably on such a high resolutions, one should use good cable, good digital->analog converter in their videocard and good analog->digital converter in their display. X200 has very poor RAMDAC in its videocard, so the image is quite noisy even on 1680*1050.

I just looked up several DisplayPort-to-HDMI and DisplayPort-to-DVI adapters and their maximum resolutions were either 1920x1080 or 1920x1200. 2048x1152 is a little higher than 1920x1200 and thus would probably not work.

There is no such thing as "maximum resolution" of DisplayPort, HDMI and DVI. There is, however, interface bandwidth; maximum bandwidth of single-link DVI is 3.96gbits/s, of HDMI v1.3 is 10.2gbits/s, of DisplayPort is 4.32gbits/s. So, basically, when one will use DisplayPort->HDMI cable, maximum bandwidth will be 4.32gbits/s.
Bandwidth required for transferring an 1920*1200 image at 60fps and 32 bits per pixel is 4.12gbits/s, so one may conduct that image is transferred with 24 bits per pixel (because single-link DVI supports such a resolution). Bandwidth required for transferring an 1920*1200 image at 60fps and 24 bits per pixel is 3.09gbps, and for 2048*1152 is 3.17gbps, so it should work flawless through DisplayPort->HDMI adapter.
Also, one can check whether SP2309W works on a native resolution from DVI with videocards which do not support dual-link DVI. It would mean that even the bandwidth of single-link DVI is enough for such a picture, so HDMI and DisplayPort should work.
And, by the way, there is no such thing as "DP-to-HDMI converters". These are just cables, because single-link DisplayPort and single-link HDMI are logically compatible. Manufacturers put that "1920*1200" or "1920*1080" messages on their cables just because it is widely-known resolution (and the next widely-known resolution is 2560*1600, and probably will not be supported by such a cable, because it involves dual-link). That does not mean the cable won't work with higher resolutions: it will, as long as such a resolution/framerate/color depth is supported by both single-link DisplayPort and single-link HDMI.

penartur wrote:X200 has very poor RAMDAC in its videocard, so the image is quite noisy even on 1680*1050.

I just tested my HP Mini 5101's ability to drive my sp2309w through an average-quality VGA cable. Image quality is not perfect but nonetheless decent. If I look very closely, I can see that some lines and edges have shadows, but that's only if I look very closely. At a normal viewing distance of 1 to 2 feet, the screen looks okay to me. So, if the OP is still following this thread, I recommend him to give VGA a try before buying any DisplayPort adapter, since what's "quite noisy" to you may be acceptable for others.

penartur wrote:Manufacturers put that "1920*1200" or "1920*1080" messages on their cables just because it is widely-known resolution (and the next widely-known resolution is 2560*1600...

Well, both 1920x1200 and 1920x1080 are widely known, so there is no reason why an adapter that can support both of these resolutions would be stated to support only up to 1920x1080. I agree with your bandwidth rationale and do think that these adapters should work fine for the OP, but they are not guaranteed to work. If I were in the OP's shoes, I would rather try the X200's VGA output first to see if I like the result. If I don't, then I would look into buying an adapter for the DisplayPort output.

pianowizard wrote:I just tested my HP Mini 5101's ability to drive my sp2309w through an average-quality VGA cable. Image quality is not perfect but nonetheless decent. If I look very closely, I can see that some lines and edges have shadows, but that's only if I look very closely. At a normal viewing distance of 1 to 2 feet, the screen looks okay to me.

It depends on the picture. Try to look at solid black background, the artifacts are easier noticeable with such picture.

Well, both 1920x1200 and 1920x1080 are widely known, so there is no reason why an adapter that can support both of these resolutions would be stated to support only up to 1920x1080.

Some manufacturer knows that there is some HD and FullHD thing, so they just put a FullHD message on the cable.
If it will work with one cable, it will work with other. These cables do not have any logic inside, it is just adaptor, it just connects pins of DisplayPort with corresponding pins of HDMI. There is no any knowledge of resolution or bandwidth etc on the cable level.
It is like avoiding to purchase an ethernet cable which states "supports media sharing", because there is no explicit claim about network printers support.
So, if videocard supports such a resolution on a single-link DisplayPort output, and display supports such a resolution on a single-link HDMI input, then it will work independent of cable purchased, even if it states "up to 800*600, guaranteed to work".