Clevo M860TU and 9600M GT: how to get WQHD (2560x1440) working

Hey guys,

I try to set up a Samsung screen with native WQHD resolution (2560x1440) together with my Clevo M860TU notebook. It has an NVIDIA Geforce 9600M GT inside. DVI and an HDMI connectors are on the outside.

The problem: I cannot push the resolution beyond 1920x1080. I believe all requirements are met (DVI-D dual link output, DVI-D dual link cable). I would like to find out if this is a hardware or driver issue and would like to discuss this with you.

HDMI 1.3 or DVI dual link are required to drive such a high resolution. According to the Nvidia specifications of the 9600 GT , it supports dual-link DVI. The first weakness in my argumentation: I have to assume that the 9600 M GT also supports it, as their specifications are unclear. About four years ago, the same topic was already discussed in this forum, without coming up with a solution. However, also in this old thread, people were pretty sure that the M860TU has a dual-link DVI output.

Just to make sure that the screen and the cable is fine: I connected the screen with the one and only dual-link DVI-D cable I have to another computer with an ATI Radeon 4850. Without installing any screen driver, the resolution was automatically set to the native screen resolution, i.e. WQHD. -> screen an cable are OK.

The most important thing to find out for me is if that DVI output of the M860TU/9600M GT really is a dual-link DVI output. What can I do to find this out? Is there special software for this? The screen does not show this information. Neither I could find this information in the NVIDIA control panel (it just says "Connector: DVI - PC display". Do you have more ideas?

For the experts among you: this is the support manual of the M860TU, containing circuit layouts: http://tim.id.au/laptops/noname/clevo m860tu.pdf

Can someone of you 'see' from these electrical connection schemes if at least 'electronically' this DVI connector has all necessary PINs connected for being dual-link?

Another option for me would be to use the HDMI output of the notebook. However, two problems arise:

• the Samsung screen I have does not have HDMI input. It has displayport and DVI input. I know that HDMI is DVI + additional features, so in principle I could solve this via an HDMI to DVI adapter. But before I buy one:
• HDMI 1.3 is required for such a high resolution -- how do I find out if my notebook really supports HDMI 1.3? Is there software for this?

Thanks for your help!

Edit:
I just realized that a HDMI1.3 -> DVI dual link adapter is not achievable. As HDMI basically is 'single link', every kind of passive HDMI->DVI adapter out there always only makes use of DVI single link. So, if HDMI output is WQHD, this signal will be forwarded only trough one DVI channel, which does not work on the other end (the screen).

 

http://forum.notebookreview.com/son...ithout-vidock-works-but-i-need-some-help.html <- You could try this. Try make a custom resolution in the NVIDIA Control Panel with a lower refresh rate. Maybe 24 or 48Hz.

 

Thanks for the suggestion. Unfortunately, my screen (Samsung S27A850D) does only support a very limited vertical frequency range: 56 to 76 Hz (from the specifications in the manual). I tried, however, to force it to lower freshrates. It then just shows black and informs me that the optimal settings is 2560x1440@60 Hz.

Thanks, nevertheless.

Anyone, is there software or unambiguous hardware characteristics that tell me exactly

• if my DVI port is dual or single link and/or
• what the specification (version number) my HDMI output is?

It can't be that people have to try this out. One must be able to know.

 

HDMI is 1.3 from Custom Laptop Clevo M860TU Core™2 Gaming Notebook, 15.4" WSXGA+/WUXGA TFT Glossy LCD, GeForce® GTX 260M / Quadro® FX 2700M Graphics by AVADirect as long as the downgraded laptop video card supports HDMI 1.3.

Regarding DVI single vs. dual link D901c has dual link with the poster's observation "Assuming you have at least an 8800M GTX"
http://forum.notebookreview.com/sager-clevo/418211-d901c-dvi-max-res.html
NVIDIA GeForce 8800M - Technical Specifications

The Nvidia 9600M GT page specs doesn't specify which link is supported, although the equivalent desktop chips, e.g. 8600 GT and 9500 GT, support have both dual and single link DVI ports - maybe only the single link port has been made available for 9600M GT.

In conclusion, M860TU could offer dual link if you have a stronger video card such as 8800M GTX and later.

 

Thanks, mmarchid, for your time.

That's true (and I hate NVIDIA a bit for the fact that they do not list the full specifications of the 9600M GT on their website). I will try to contact NVIDIA and ask about DVI on the 9600M GT. The DVI output connector on the back of my notebook 'looks like' being dual link. I am still wondering if anyone can use the information provided in http://tim.id.au/laptops/noname/clevo m860tu.pdf in order to find out if the electrical connectivity of this port is sufficient for dual link.

 

I closely looked at the DVI port circuit layout of the Clevo M860TU again (in the service manual). It revealed that pins 4, 5, 12, 13, 20, 21 are not connected. According to Wikipedia, those pins make up one of the two data links. I documented my findings in a blog post at Does my notebook support dual-link DVI? » gehrcke.de.

Problem "solved" partly. Now I have to find out if my HDMI port is of version 1.3 or lower.