Dual Link DVI with 4870?

[macbrush]

I have asked the same question in the 4870 post, but it got buried very quickly, so I decided to post a topic about it.

 

Anyone have experience with DL DVI on a 4870? Success or not, please share your experience.

 

I have a Sapphire 4870 512MB w/ 2 DVI ports. I got both ports work, dual display, QE/CI, resolution change, rotation, sleep, and all. But when I plug a dual link monitor into it, I get some strange behavior, and I could never get it to display 2560 X 1600 properly.

 

Scenario 1: Only a 30" is connected to either port.

result: I only get rubbish on the screen after kext loading.

 

Scenario 2: 26" on primary port, 30" on secondary port.

result 1: 30" get recognized as 1280 X 800, and both display usable.

or result 2: 30" get recognized as 2560 X 1920 and only 26" is usable, 30" gets black screen

 

Scenario 3: 30" on primary port, 26" on secondary port.

result: 30" display rubbish, and 26" get black screen

 

I will try again tonight, and see if I could manage to get some ioreg output posted.

 

Thank you very much in advance for any suggestion or hint you might have.

[netkas]

>result 1: 30" get recognized as 1280 X 800, and both display usable.

 

usual result when dual-lin dvi isnt supported.

[macbrush]

Thank you very much for the tip. So if that's the case. Do you think it is a problem with the current developer driver, or it is a problem with Natit?

 

Thanks in advance

 

>result 1: 30" get recognized as 1280 X 800, and both display usable.

 

usual result when dual-lin dvi isnt supported.

[jerrah]

I have the same problem unfortunately. It's a driver issue.

 

Going back to my 8800GT until we can work out the 30" problem.

 

A fix here: http://www.insanelymac.com/forum/index.php...5477&st=160 ?