Resolved How to power a GTX 780 Ti

[Project Alice]

Hi all,
I have a 2008 Mac Pro 3,1. It currently has a 3GB GTX 1060 installed, powered by the 2 on board 6 pin power connectors. Because it seems nvidias drivers will be no more, I'm sticking the 1060 in my PC and getting a 780 Ti for the MP.

According to the internet, the 780 requires a 6 pin and an 8 pin, OR 3 6 pins. I found something about an adapter that uses 2 sata ports for power; this WILL NOT work for me. All 4 of my sata slots are in use, I'm even using the 2 extra ones for an SSD and blueray drive in the optical bay. I cannot free up any bays, I need the those 6 drives installed.

Anyone else have their Mac Pro running a 780 Ti that can help me out?

 

[OS6-OSX]

Hi all, Anyone else have their Mac Pro running a 780 Ti that can help me out?

Don't have the 780ti but at one time had my 980ti in the 2008 3,1. If you look where the 6pin to 6 pin is plugged in (on the MP) you will see another identical port. Get a 6pin to 8pin cable and plug the 6pin end into that identical port (MP) and the 8pin end into the 780ti. Now both ports will be dedicated to the 780ti.

 

[verdejt]

6 pin to 8 pin like this one.

https://www.amazon.com/6-pin-8-pin-...075C1GH00TK&psc=1&refRID=PT92BPQT6075C1GH00TK

 

[MIKX]

I power my Sapphire Dual- HD 7970 this way . seems the safest.

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1. From onboard dual 6 pin power sockets
Dual mini 6 pin to 8 pin > GPU 8 pin socket

2. Dual SATA to 6pin >. GPU 6 pin socket.

====================================

I now boot from a PCIe M.2 Samsung 970 EVO and my other SSDs live in the DVD enclosure but I do have one spinner HDD installed in SATA slot 4. I have 3 SATA power sockets ( one is dedicated to powering my USB 3.0 card ). So I have three SATA sockets available for the " dual SATA to 6 pin" cable,

Everything works.

I feel the single 6 pin to 8 pin from one on board 6 pin socket is playing with ( real ? ) fire.

I worry about the load on the motherboard traces when the GPU is under high load/stress.

 

[startergo]

I power my Sapphire Dual- HD 7970 this way . seems the safest.
I worry about the load on the motherboard traces when the GPU is under high load/stress.

Why so? You don't go over the design capacity :
1. From onboard dual 6 pin power sockets
Dual mini 6 pin to 8 pin > GPU 8 pin socket (150W design capacity)

2. Dual SATA to 6pin >. GPU 6 pin socket. (108W design capacity)
And the card requires 150 W supply on the 8 pin and 75W supply on the 6 pin.

 

[Project Alice]

I think the card needs Dual 8 pin? If so, I wouldn't be able to do dual 8 pin unless I did single 6 to single 8. Since I only have Dual 6pins on the board....