hi there,
I have recently done a fresh install of mountain lion, I have a macpro early 2008, 8 core, 8800gt 512mb card. Used to have lion and dual monitor setup worked fine. After the upgrade, one of the monitors doesnt get recognised. I swapped cables and did everything, ** now one of the dvi ports doesnt work. Please Help!
Abdul
Mac Pro, OS X Mountain Lion (10.8.3)
you know 8800's do fail? that it might be time to bake it in the oven and see though might want to get Apple ATI 5770 upgrade.
it cant be cos it works with lg tv but sets the resolution 800x600 by default. If i change it 1920x1080 it makes it square and not widescreen as it was before mountain lion. So i am guessing it is unsupported resoltion. How can I reset it to default?
Make sure you allow the displays to have resolutions that are separate from each other by unchecking:
[√] Mirror displays
hi grant, I did that. But still same problem. If i may add, i have the lg tv connected via vga adaptor
VGA can't go up any higher on most TV sets. Standard broadcast (which was what VGA was good for) was 640 by 525, and you have stretched it to 800 by 600. The interface you chose is the limiting factor.
I was using this setup with lion and snowleopard, no problems, i used it with dvi adaptor. The problem only started after I installed mountain lion. Is there anyway of resetting the gpu or bios memory, as it recognises the lg but not dell monitor. I have two dell monitors that used to work with lion. no problem. But not in mountain lion.
Then go back to the DVI adapter and you will get better resolution, presuming your Hardware is still working properly. VGA cannot do what you desire.
There is no intervention available and none required. Mac OS X uses a highly paramterized Graphics driver. When connected, and again when you click ( Detect Displays ) Mac OS X asks the display to provide its capabilities and its name.
About this Mac > ( More info ) > Graphics and Displays...
... should list the name of the device and its capabilities.
If the displays do not appear BY NAME under this heading, they are not being recognized, and cannot be configured automatically.
.
... and if they do not apear, this is often a problem that the TV is not set to that specific input, and therefore does not answer when you say ( Detect Displays).
hi grant, thank you for your support, i guess i didnt make myself clear. problem is the macpro doesnt detect the second dell monitor but if i plug the the tv with dvi adaptor, it detects but gives me res of 800x600. This never happened before mountain lion. Before mountain lion, both dell monitors worked fine, both are identical . I swapped the ports, so both dell monitors work, but one dvi ports doesnt detect the dell any of the dell but detects the lg with dvi adaptor. So gpu is working. This problem started when i upgraded to lion, i have leopard installed in another hdd, that has the same problem, so must be system.
NVIDIA GeForce 8800 GT:
Chipset Model: NVIDIA GeForce 8800 GT
Type: GPU
Bus: PCIe
Slot: Slot-1
PCIe Lane Width: x16
VRAM (Total): 512 MB
Vendor: NVIDIA (0x10de)
Device ID: 0x0602
Revision ID: 0x00a2
ROM Revision: 3233
Displays:
DELL E248WFP:
Resolution: 1920 x 1200 @ 60 Hz
Pixel Depth: 32-Bit Color (ARGB8888)
Display Serial Number: FY1317CH0KUS
Main Display: Yes
Mirror: Off
Online: Yes
Rotation: Supported
Please help.
I asked for you to show the output of graphics and displays, and you cut off the last line that would show what was really happening on the second port.
The more you write about what you have connected where using what adapters, the less I understand.
I think you should take your equipment to the genius Bar where they can SEE what you are talking about.
What I posted initially is what you see when both dell monitors are connected. So basically the 2nd monitor doesnt get detected. The dell monitors are connected straight as they have dvi cable as native.
This is what happens when I connect the one dell and the lg tv. Hope this helps.
NVIDIA GeForce 8800 GT:
Chipset Model: NVIDIA GeForce 8800 GT
Type: GPU
Bus: PCIe
Slot: Slot-1
PCIe Lane Width: x16
VRAM (Total): 512 MB
Vendor: NVIDIA (0x10de)
Device ID: 0x0602
Revision ID: 0x00a2
ROM Revision: 3233
Displays:
VGA Display:
Resolution: 1920 x 1080 @ 60 Hz
Pixel Depth: 32-Bit Color (ARGB8888)
Mirror: Off
Online: Yes
Rotation: Supported
DELL E248WFP:
Resolution: 1920 x 1200 @ 60 Hz
Pixel Depth: 32-Bit Color (ARGB8888)
Display Serial Number: FY1317CH0KUS
Main Display: Yes
Mirror: Off
Online: Yes
Rotation: Supported
VGA is generated directly by the graphics Hardware, and is supplied on the bar at the end of the connector and basically the four pins around the bar. The adapter used is only an adapter, no signal conversion is performed. VGA working or not working is not particularly meaningful.
What does that listing show when you:
1) connect the display you care about to the port you really want to use (presumably the second DVI).
2) deliberately switch the monitor so that it is accepting input from the port you connected it to
3) Press the ( Detect Displays ) button at the macintosh end.
If the name of the display is not showing up, something is fundamentally wrong with the setup or the secondary channle is not working to accept the display_name and capabilities.
If the name shows up but no picture, it is a simpler problem, possibly a bad adapter or cable.
If the problem follows the adapters or cables or the other Graphics card port, you can isolate it that way.
If the problem does not follow the display or cable or anything except it always fails on the second graphics port, then the DVI portion of the second graphics port is the problem.
Dual monitor in mountain lion
