5870 with dual monitor - works but doesn't

[infra]

My reference 5870 is configured correctly and dual monitor support is working well but I'm having a bit of a hang upon booting into SL.

I have two 27" Dell 2707WFP's and they are connected via DVI. Whenever I put into SL, after the apple loading screen, one of the displays blanks out. It's receiving a signal, but it's just a black display. I can fix it by removing the DVI cable and plugging it back in and presto, all is swell. I've also tried using a DVI-VGA connector but I didn't have any luck.

Cheers.

 

[Seekyu]

which method u use? mutibeast?
and do u try one mon use DP and other use DVI?

 

[infra]

which method u use? mutibeast?
and do u try one mon use DP and other use DVI?

Yes, I followed the guide MacMan posted in the stickies in the Graphics section, which uses the MultiBeast method.

Unfortunately, I don't have a display port cable/dongle to use at the moment. I used the iBoot 5xxx-3 loader for the install.

 

[infra]

Just an update:

I'm waiting for my DisplayPort-to-DVI connector to come in, so hopefully that will solve the monitor issue I'm having on bootup.

I did find something interesting though. On Bootup, one of my monitors doesn't turn on, this is already clarified, but after a while, my Dell 2707WFP reports that the signal it gets is "Not Supported" and requests that I set it back to 1920x1200.

Is it possible that the resolution, on bootup, is being set to an unsupported resolution? Does it some how correct itself when I replug the monitor in question? It obviously does, but I'm curious.

Maybe a small script that outputs the current resolution of each monitor on bootup to a text file?

Not sure what to make of this, but hopefully it'll be a problem behind me when I get my DP adapter.

Cheers.

 

[ludiol]

I have a similar problem. My configuration is a HIS HD5850 with a Samsung 24" 1920x1080 (working perfectly as main screen) and as secondary screen I have an Eizo 24" with 1920x1200.

At restart my 2 screens are showing the Apple Logo, but as soon as I log into my account, the Eizo screen starts showing grey static. When I open the Monitor prefs and change to a lower resolution and then I change back to max resolution everythings works fine. I don't like the idea of unplugging the DVI at every restart.

This is the last hickup (besides not being able to use my 3 monitors)

 

[kitkonis]

How long I will must wait for a fully functional 5870? I will use dual monitor too.

 

[infra]

Just an update.

My DisplayPort to DVI adapter came in today. Plugged it in, rebooted, and I received the exact same results as if my monitor were plugged straight into the DVI port. Using a DisplayPort adapter doesn't seem to make any difference. Upon reboot, the one screen goes blank (or flickers then goes blank). Only when I unplug the DVI cable and plug it back in, will the display turn on correctly.

Any ideas on what to try next? I can't use HDMI since my monitors don't support it... and I'm not sure about spending more coin on an HDMI to DVI converter.

 

[vindoan]

I have this experience with my XFX 5870 and two Dell 3007 connected to the two DVI ports.

I noticed, that if I put the monitors to sleep, and wake them, then the image reappears on the monitors. Also, if I unplug and reconnect the DVI cable at the back of the graphics card, I would get images back on the monitor.

As a work around, I setup Expose to "Put Display to Sleep" as my bottom right, active screen corner. After booting up the computer, and after the screen goes black, I put the monitors to sleep by dragging my mouse pointer to the bottom right corner, then mouse the mouse again to reactive the monitors.

 

[infra]

I have this experience with my XFX 5870 and two Dell 3007 connected to the two DVI ports.

I noticed, that if I put the monitors to sleep, and wake them, then the image reappears on the monitors. Also, if I unplug and reconnect the DVI cable at the back of the graphics card, I would get images back on the monitor.

As a work around, I setup Expose to "Put Display to Sleep" as my bottom right, active screen corner. After booting up the computer, and after the screen goes black, I put the monitors to sleep by dragging my mouse pointer to the bottom right corner, then mouse the mouse again to reactive the monitors.

I'd like to confirm that vindoan's workaround works quite well! No more crawling under the desk!

Would be sweet to map it to a four-finger button press on my Magic Mouse via BetterTouchTool in the event I accidentally tuck my mouse away in the corner for a second too long.

Cheers for that!

 

[vindoan]

Glad the workaround works for you.

The ATI 5XX0 drivers or Chameleon (I'm not sure which one) doesn't handle the switch from the BIOS resolution to the desktop resolution. Resulting in a black screen, when entering the desktop.

Some have reported adding Graphics Mode key/string pair to /Extra/com.apple.Boot.plist solves this problem:

<key>Graphics Mode</key>
<string>1920x1200x32</string>

But adding the Graphics Mode did not work for me. I think the Graphics Mode string only works if your BIOS supports the resolution/bitdepth. Typing "?video" sans quote at the Chameleon boot screen will show you the VESA modes that your BIOS supports. My BIOS did not support my desktop resolution. Hence I had to use the workaround with putting the monitor to sleep.