Late-2013 Mac Pro with Sonnet xMac Pro Server with 980 Ti via TB2

[ibuick]

Hi,

I am struggling to get a GTX 908Ti work with my Late-2013 Mac Pro 6,1 under OS X. 10 hours past, and I've been unsuccessful so far. Please help me, any advice will be appreciate. 😄

My hardware configuration is almost the same with @martona in his post http://forum.techinferno.com/provisional-guides/10351-2014-mac-pro-titan_x%4016gbps-tb2-sonnet-xmac-pro-win-8-1-%5Bmartona%5D.html.

Mac Pro Late-2013 6,1

Sonnet xMac Pro Server enclosure, it has a bult-in PCIe expansion, it is just the same as Sonnet III-D

NVIDIA GTX 980Ti (Inno3D)

External PSU Corsair RM650 (8+6 pin) to provide power to the graphics card.

The OS is OS X 10.10.4, I am following @goalque 's guide and use the script with -a argument.

The script works fine, And the hardware (including the PCIe expansion and thunderbolt) work fine also. I can see the LED indicator of the GPU and the fan running.

Things got weird…

If I plug the 8+6 pin power supply from PSU to the GPU, the System Profiler cannot find anything related this device. The Thunderbolt Tab shows nothing related, the PCIe Tab shows nothing also.

If I unplug (disconnect) the 8+6 pin power supply from PSU to the GPU, the System Profiler can recognize this device as a GPU but leaving it status as Kext NOT Loaded.

I think this may be related to the power supply of the PSU. It has a button for on/off. So, do I need a jumper also ? I saw many implementation has a jumper to turn on/off the PSU.

Am I missing something obvious? I seem to be doing things according to what others have been posting here.

[SimonSays]

You most certainly need a jumper cable....

The GPU is getting NO power as the PSU is not on.... Fix that and I'm sure you will boot.

[ibuick]

Thanks Simon, I just make a paper clip but no lucky, OS X still not recognize my card. Do I have additional mod for the enclosure ?

Here are what I have got now:

If I plug the GPU to III-D directly without 8+6 Pin PSU supply, the OS X recognize the GPU but just

show it as a Nvidia Chip with JUST 256MB vram.

If I plug the GPU to III-D directly with 8+6 Pin PSU supply, the OS X's System Profiler shows nothing about the card. The PCIe tab of System Profiler now just shows two built-in D500 GPU.

I am now considering wether I have a DOA(Damaged on Arrival) PSU. I just bought a diag switch to test it.

Would you mind giving me some other advices? Thanks very much.

[juniordiscart]

@ibuick

As SimonSays says, I'd first make sure that the PSU surely is turned on and giving power to the graphics card. I see you have a Corsair RM PSU, which means the cooling fans remain idle when no significant load is put on them. So you're never really sure whether the PSU is turned on or not. I would make sure that you applied the paperclick trick correctly by connecting a simple fan to one of the molex connections. If you applied the paperclip correctly to the PSU, then the fan should start spinning, and then you can make sure your graphics card is getting the power from the PSU. Sometimes, you need to fiddle a little with the paperclip to make sure it has contact on both pins of the PSU.

If, after this it still doesn't work, you might consider that some parts are broken.

[ibuick]

Latest update here.

Thanks @SimonSays and @goalqu. I have done it.

Actually, it's my fault to connect the CPU's 8 pin supply to the GPU, today I changed it to PCIe 8 pin supply and it worked immediately.

Thanks @juniordiscart, now I know the Corsair's "fan issue".