Anyone have dualx1900xt

digitaltrader

macrumors newbie
Original poster
Aug 22, 2006
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I have a single x1900xt and now have 3 monitors I need to power. Is it possible to combine NVIDIA cards and ATI or do I need to pruchase another x1900xt? Anyone have a similar configuration yet?
 

Renovatio

macrumors regular
Jul 21, 2006
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Granger, IN; USA
digitaltrader said:
I have a single x1900xt and now have 3 monitors I need to power. Is it possible to combine NVIDIA cards and ATI or do I need to pruchase another x1900xt? Anyone have a similar configuration yet?
If I recall correctly, you can't have more than one x1900xt because it using the 16x PCI slot and there is only one 16x slot in the Mac Pro. I believe your only option would be to buy one of the NVIDIA cards.
 

digitaltrader

macrumors newbie
Original poster
Aug 22, 2006
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Is there possibly a cheaper ATI video card I could use to run the 2 smaller 20 inch monitors and then the x1900xt to power the 30 inch. I have read elsewhere that nvidia and ati cannot be combined.
 

Spanky Deluxe

macrumors 601
Mar 17, 2005
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London, UK
If there's enough space in the top PCIe slot then two ATI X1900s should work since you can set it up so that the slots have x16 x1 x1 x8 bandwidth and the x8 bandwidth would be enough. It might be slightly bandwidth limited but not that badly.
 

digitaltrader

macrumors newbie
Original poster
Aug 22, 2006
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Im surprised no one else has ran into a similar problem. Would it be better to run the 2 20inch of the 8x and the 30inch off the 16x or reversed.
 

YoYoMa

macrumors 6502
Aug 3, 2006
386
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Does the Mac Pro motherboard have multiple places to plug the video card power cord up to?
 

Spanky Deluxe

macrumors 601
Mar 17, 2005
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London, UK
YoYoMa said:
Does the Mac Pro motherboard have multiple places to plug the video card power cord up to?
Yes, it has two power connectors for video cards. I'd run the 30" on the primary display (i.e. the x16 speed slot) and the other two in the x8 slot. Both cards should perform very similarly, I doubt the bandwidth difference will have much of a slowdown. You would, however, want your main display (the 30") powered by its own graphics card.
 

studiox

macrumors regular
Aug 3, 2004
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Stockholm / Sweden
Spanky Deluxe said:
Yes, it has two power connectors for video cards. I'd run the 30" on the primary display (i.e. the x16 speed slot) and the other two in the x8 slot. Both cards should perform very similarly, I doubt the bandwidth difference will have much of a slowdown. You would, however, want your main display (the 30") powered by its own graphics card.
**** didn't know that. Now i need a cable for that i guess
 

Pressure

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May 30, 2006
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Renovatio said:
If I recall correctly, you can't have more than one x1900xt because it using the 16x PCI slot and there is only one 16x slot in the Mac Pro. I believe your only option would be to buy one of the NVIDIA cards.
The Mac Pro has 4 PCI-Express 16x slots.

However, if other cards are inserted it will divide these amongst the used PCI-Express 16x slots e.g. if two PCI-Express graphic cards are inserted they both will be set to 8x and so forth. Thus dividing the available bandwidth between the cards.
 

omfgninja

macrumors member
Aug 9, 2006
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Pressure said:
The Mac Pro has 4 PCI-Express 16x slots.

However, if other cards are inserted it will divide these amongst the used PCI-Express 16x slots e.g. if two PCI-Express graphic cards are inserted they both will be set to 8x and so forth. Thus dividing the available bandwidth between the cards.
uh....

I might be wrong. But I thought there was some kinda utility that let us do the lane changes ourselves?
 

Spanky Deluxe

macrumors 601
Mar 17, 2005
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London, UK
omfgninja said:
uh....

I might be wrong. But I thought there was some kinda utility that let us do the lane changes ourselves?
What Pressure said was wrong. I believe there are a total of 26 PCIe lanes available which you can set up in various configurations.
 

Neurorad

macrumors newbie
Aug 28, 2006
28
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Yes - But Windows . . ..

I have two Apple XT1900 upgrade kits. Installing the second card can be hazardous - it is a tight fit for slot 3. Removing the adjacent SATA drives will help. The release tabs on the slot sockets can be easily broken off if you do not have good access - I have proven that.

1. Yes, you can install two ATI cards, one in the 16 lane slot 1 position, and the other in either slot 2 or 3. It will not fit in slot 4. Slot 2 shares bandwith with slot 1 and can give you up to 8 lanes each. Slot 3 can give your 4 lanes at most for a card, but leaves slot 1 at 16 - probably the best if a secondary monitor is used on the slot 3 card. BUT - only the Mac OS works properly. Windows XP Pro get confused and the device manager has several additional unusable system components, including the 16 lane PCI express slot. Bootcamp 1.1.1 does not correct this. In Windows, you cannot properly activate a monitor on the second card or properly adjust to monitor attached to the slot 1 card. Not very useful. The grossly reduced bandwith of the second card in Mac OS X and the conflicts in Windows makes this useless for anyone who wants to boot into Windows.

More info: http://developer.apple.com/documentation/Hardware/Conceptual/HWtech_PCI/Articles/pci_implementation.html

There is an application that helps manage the card settings called "Expansion Slot Utility" that appears after you add a card. It is in the /System/Library/CoreSerivces folder.

2. You CAN run the ATI X19000XT in slot 1 and put a Nvidia 7300 in slot 4. Again, Mac OS X handles this without a problem, but - surprise - Windows chokes and cannot use both at the same time.

Next, an RMA for the second card. Any suggestions from anyone??
 

jroad

macrumors member
Mar 24, 2006
49
0
Neurorad said:
2. You CAN run the ATI X19000XT in slot 1 and put a Nvidia 7300 in slot 4. Again, Mac OS X handles this without a problem, but - surprise - Windows chokes and cannot use both at the same time.
So you say windows cannot use both at same time, does this mean windows will not boot/run? In other words, can you still use windows, but can only get it to use one card at a time such as the ATI x1900xt or will windows refuse to boot properly?

Thanks for your insight because I am interested in a triple monitor setup.
 

Neurorad

macrumors newbie
Aug 28, 2006
28
0
Dual Cards

Windows does boot. WIth two ATI cards, only one the slot 1 card is active (tested with only one monitor hooked to each). The resolution is too low and cannot be properly set. With an ATI and Nvidia card, I was able to boot into the ATI card on one monitor, again only is low resolutions. I reinstalled the Nvidia drivefr then windows would boot only to the Nvidia card,a lthough at decreased resolution. I did not try the Nvidia card in slots 2 or 3.
 

jroad

macrumors member
Mar 24, 2006
49
0
Neurorad said:
Windows does boot. WIth two ATI cards, only one the slot 1 card is active (tested with only one monitor hooked to each). The resolution is too low and cannot be properly set. With an ATI and Nvidia card, I was able to boot into the ATI card on one monitor, again only is low resolutions. I reinstalled the Nvidia drivefr then windows would boot only to the Nvidia card,a lthough at decreased resolution. I did not try the Nvidia card in slots 2 or 3.
Thanks for the information. Regarding the ATI + Nvidia combination you have shown that in OS X you can use both cards with one monitor attached to each.

In Bootcamp, it seems you have shown that in your setup:
1) Windows will detect only one display at a time
2) Resolution was very low

My hope is that this is just a driver issue that can be sorted out. So, I have some additional questions if you (or anyone else with similar setup) could possibly answer.

In XP, with both video cards installed:
* Does the Device Manager properly recognize one or both cards?
* In Display Properties->Settings:
- is your display properly recognized?
- are you able to fix your resolution problem with the slider?
- does it show both displays, but one is disabled?
 

Neurorad

macrumors newbie
Aug 28, 2006
28
0
ATI and Nvidia

With an ATI XT1900 in slot 1 connected to a 30" ACD and a Nvidia 7300 in slot 4 connected to a 23" ACD:

-Only one monitor at a time was recognized. At first, only the 30" ACD connected to the ATI was seen, but a a low resolution. Moving the slider to a higher resoltion actually magnified the desktop! The resolution was not any greater. Very strange behavior. The Nviia card was not seen by Windows at this point.

-I ran an Nvidia driver installer, which upon rebooting, only the 23" ACD connected to the Nvidia was active, also with low resolution similar to the ATI. The ATI card was not visible by Windows at this point.

In summary, only one card at a time could be recognized and only at a low resolution.