Problem: M6600 with 2560x1600 screen on dockingstation

i have a dell m6600 for half a year now and every single day i have the same problem:

when i boot up my machine in the morning, the external screen on the docking station (LG 30" with 2560x1600 resolution, connected via displayport with a displayport-to-dualdvi adapter) is not working.

so i have to remove the displayport connector from the dockingstation and reinsert it. 97%: the display is then recognized and working. 2%: i have to reboot the machine and try again. 1%: it's immideately working when i boot up my machine.

theres a thread on the dell forum with this problem - but no real fix (Re: Dell Precision M6600, Optimus and DVI/Displayport not initialed at boot time - Laptop General Hardware Forum - Laptop - Dell Community)

this "problem" is really freaking me out - does someone have the same problem and/or a solution? (the "disable-optimus in bios trick" is not working for me...)

thanks for your help!

 

I would check if the displayport-to-dualdvi adapter is working correctly, just use the display port directly on the laptop not on the dock. If you have the same issue, that it'll randomly want to work I suggest you speak to the manufacturer of that adaptor. As on the site they did say to overriding this issue was to disable the optimus, which you have done so already...

 

Anyone know if this issue exists with monitors running 1920 x 1200. I am considering getting a dock & 3 u2412's, running two off the dvi or displayport & one off of the VGA on the dock.

 

i dont think this is a general issue. never heard of it before.

 

I used it with the Dell U3011 1600p screen and saw no problem. I am assuming the LG does not have the display port?

I read somewhere that IPS screens must use display port. Not sure if this is panel related or just with Dell's monitors, but that is the reason why HDMI or DVI will only get up to 1200p.

 

Does your machine have a quadro card & if so is optimus disabled?

The panel type (IPS, TN, ect) doesn't have any relation to the video connection. The U2412M's are IPS and have DVI & dispplay port connectors. As you mention it's the max resolution & required bandwidth that would require the use of a display port or dual link dvi ports.

 

An single DVI can handle 1920 x 1200 at 60Hz, I'm using one for my dock with a Display Port to DVI for my TN monitor.

Dellienware is kinda on the right line, but let me explain abit more. Cause it's not just the max resolution you have to take into account....
If you have a 120Hz screen, then you would need the display port or a dual-DVI set-up. Though TN are 6-bit and IPS should be 8-bit+ which is fine on a single DVI max 24-bit per pixel but an P-IPS is 30-bit which needs a display port or a dual-DVI set-up

 

tried a few things now...
seems to work when i connect the usb AND the displayport connector directly to the workstation...
when i connect anything to the docking-station it's not working any more... so i guess the dockingstation is "the problem"....

 

Yes. Quadro 2000M and 4000M running optimus.

My machines are gone so I can't test anymore..

I think the 8bit for IPS is the reason for the DP. I read somewhere that Dell decided to put in DP on all mid-high end machines so that people can use its IPS ultrasharp monitors.