Ripper2010
Your 7970 is unusual in that it has TWO 8 pin sockets. My Sapphire Dual-X 7970 has ONE 6 pin and ONE 8 pin socket.
I know this is a hassle but can you remove the GPU & take some photos of ..
1. The bottom of the card showing the two power sockets.
2. The position of the
BIOS switch; is it set to position 1 or 2 ? ( should be set to position #2)
3. The whole card from an oblique angle showing the face of the card and also the graphic ports.
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Q : What is your monitor's make & model ? What ports does it have ?
Q : How are you powering the card ? Which power cable
s are you using ?
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Best power cabling solution
From Mac Pro motherboard to GPU
1.
TWO x Mini 6pin to ONE x 8 pin to GPU 8 pin socket
( I presume that you already have this cable )
2. Remove two SATA drives - connect them to the TWO SATA cables in the DVI Drive cage.
2.1 You will now need a
TWO x SATA to ONE x 6 pin cable ( not 8pin for safety )
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2.3 : You
CAN plug a 6 pin cable male socket into the other GPU's 8 pin's female socket
BUT it must be plugged into the RIGHT SIDE of the socket.
The above cable will supply less power than a 2 X SATA to 1 x 8 pin but is safe to use and will not
trigger shutdowns.
( a 2 x SATA to 1 x 8 pin cable might draw too much power & trigger a shutdown)
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I should be able to work out a solution to your problem if I you can confirm all of the above.
It could also be that your card was not flashed correctly. I can help with that too.
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If eventually everything works out OK you can go one step further and use a
EVGs PowerLink to balance out ALL the available power supplied from the above cabling and then to the GPU.
The PowerLink was originally designed for NVIDIa GPUs but can be used with many AMD cards too.
I use the PowerLink ( depending on the situation ) with both my Sapphire Dual-X 7970 3gb & my MSI Armor RX580 8gb.
Just got the EVGA PowerLink working with my Sapphire Dual-X 7970 3gb. IMPORTANT : The power input sockets on the PowerLink are 2 X 8 Pin female and cannot be changed. The EVGA PowerLink ensures that exact power demanded by a GPU is supplied. That said, one must still supply enough power to...
forums.macrumors.com
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It would not hurt if you were to go to your Macrumors Member Profile/ SIGNATURE and write a description of how your Mac Pro is set up. Include your current Mac OS version & your bootrom version )
My SIGNATURE is at the bottom of this post.
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Please send me a PM ( private message) if you have any questions.
Myself and many other here are quite experienced with both EFI lashing & powering AMD GPUS.
