GTX 750 TI on Mac Pro 1.1 only working with 4 Lane PCIe-Slot

[alclonky]

Hi,
i got a GTX 750 TI (Palit one) for my 1.1 Macpro (2.1 with Firmware Update),
but the GPU is not recognised if i put it into a 16x or 8x PCI-e Slot.
It only work if i switch the Port to 4x or 1x.
I am on OS X 10.10.1 with nvidia web drivers

is it possible to do something about it?

 

[sarthak]

Check if you have other cards installed in the PCIe slots. If so you should get a utility upon boot to specify PCIe lane configuration. However, since you are running it on a 1,1 it is likely it's not included in Yosemite (AFAIK not required for 2008 machines).

 

[NOTNlCE]

Check if you have other cards installed in the PCIe slots. If so you should get a utility upon boot to specify PCIe lane configuration. However, since you are running it on a 1,1 it is likely it's not included in Yosemite (AFAIK not required for 2008 machines).

Ironically enough, there's a new updated version of the PCIe Lane Utility included in Yosemite. I agree though, check your configuration. Though you might not have any luck - PC cards are temperamental. I have to use my GeForce 405 in Slot 2. If I put it in Slot 1, it won't wake from sleep. Just a compromise that has to be made to keep the older towers alive.

 

[alclonky]

I checked it with the utility

Slot 1 - doestn't work (Slot1 can only be 8x or 16x)
Slot 2 - works with x1 Setting but not with x8 Setting
Slot 3 - works with x1 and x4 Setting
Slot 4 - Card doesn't fit

In Windows the Card works in Slot1 so it can't be a technical issue but a driver one?

 

[NOTNlCE]

Could be. Unfortunately, troubleshooting is a bit of a trial and error process with these kind of things. I would test as much as you can and just stick with the configuration that works BEST, whether or not it's the most optimal is up in the air.

 

[aaronlroberts]

Hey, is there any progress on this? I know this post was from 2014, but I have a mirrored case.

https://forums.macrumors.com/threads/mac-pro-2006-1-1-gtx-750-ti-please-help.2042489/