"Green Fuzzy Screen" when connecting Mac Pro to Dell 30" 3008WFP

[counterhype]

Hello everyone,

I own a MacPro1,1 that has a Geforce 7300 GT running on it. That video card comes with one Dual-Link DVI port, and anonther that is Single-Link. I just bought a Dell 30" 3008WFP monitor that has a max resolution of 2560x1900.

When I first connected, it worked great. I was getting the max res; life was good. Then I started getting this random green fuzzy screen that would come and go at whim. I couldn't reproduce it, and worse was I have not figured out a way to get rid of it. Early on, just unplugging and replugging in the cable worked. Then that stopped working. Rebooting stopped working. Once i was able to get the green to go away by powering down the display and powering it back up. Yes, totally random.

Here are some more facts:
1. Setting a lower resolution doesn't rid me of the green fuzz effect.
2. If i connect to the same monitor using the single-link DVI port, everything works great, but only reaches 1920X1600 (as expected).
3. Connecting to different monitor using the Dual-Link DVI port works fine, albeit that the other monitor has a lesser max resolution.
4. I'm running Snow Leopard 10.6.3 and I have all my software updates in place.
5. I've attached a screenshot of what this looks like.

Anyone's help would be greatly appreciated. I don't know if this is the video card or the display.
thank you

 

[MythicFrost]

Sounds to me like the monitor might be faulty or perhaps your graphics card isn't enough to power it? I thought the 3008WFP had a max resolution of 2560x1600?

Have you tried contacting Dell support?

EDIT: Leaning more towards your graphics card not being able to handle it, try googling something like "3008WFP with GeForce 7300 GT problems"

 

[maghemi]

I'd be very surprised that the video card couldn't handle it.

Have you tried a different DVI cable? that could also be faulty? Do you have another computer that you could try the screen on?

 

[flatfoot]

5. I've attached a screenshot of what this looks like.

Make a "real" screenshot (cmd-shift-3) and have a look at it on another computer/display. If it shows the colour distortion, there's something wrong with the graphics card, otherwise it's the display that's faulty.

 

[counterhype]

MythicFrost, I've done that search and haven't found anything that offers guidance.

Maghemi, I did use a different DVI cable, same issue. I've tried the screen with my MacbookPro, but I am using a mini-displayport to displayport wire for that (not using the DVI ports), and it works great at max resolution. I don't have another computer to test the DVI port with.

Flatfoot, I tried what you said and the screenshot showed up without any distortions; just a normal screenshot. Is that enough to conclude its the display though?

 

[Cindori]

Flatfoot, I tried what you said and the screenshot showed up without any distortions; just a normal screenshot. Is that enough to conclude its the display though?

no, but enough to conclude it's not the graphics card.

what you are looking at is a problem somewhere after the signal is sent by the graphics card. so either, graphics card port, display cable, monitor port, or monitor itself.

I will sometimes get this green distortion, becuase I am using a 10meter dvi cable that is not very good quality. (dvi gets very weak at 10+meter). but re-establishing connection, aka turning off screen or reseating cable, always fixes this for me. i have a 24".

 

[counterhype]

so either, graphics card port, display cable, monitor port, or monitor itself.

Any recommendations on isolating which one it is. I'm ruling out the display cable because I tried with 2 new ones, and they are both short (1-2 meters). I think i can rule out the monitor port as well because there are two DVI ports on the monitor, and they both do not work.

Graphics card works, but perhaps its the port? Have you ever heard of a Dual-Link DVI port working when attached to a monitor's Single-Link DVI port but not working when attached to another monitor's Dual-Link DVI port? Something maybe with voltgage, capacitance, etc.?

Since the monitor works on other ports (DisplayPort), can we rule out the monitor as well?

Thanks for your help

 

[counterhype]

Another interesting thing is that if look at Profiler, it seems that the MacPro doesn't know what monitor I'm hooked to, something that usually worked before with other monitors. Below is from Profiler. Note that I'm plugged in using the Single-Link DVI Port right now. Is it possible that I don't have drivers for this monitor? If so, maybe thats causing it? If so, how do I update drivers on Mac?

Displays:
Display Connector:
Status: No Display Connected
Display:
Resolution: 1920 x 1200 @ 60 Hz
Pixel Depth: 32-Bit Color (ARGB8888)
Main Display: Yes
Mirror: Off
Online: Yes
Rotation: Supported

 

[Terminal.app]

I saw that once when I first connected a Dell to my MBP with the mini DP > DVI adapter. All I had to do to fix it was shut down and reboot, and it fixed the issue. Odd, and I've never seen it since.

 

[counterhype]

Just connected to a windows server 2008 machine with the same cable, and the same DVI Port on the monitor. Works perfectly at 2560x1600.

This must be the graphics card, unless its a driver problem. Any ideas?