Safest way to power an hungry gpu 8 + 8 pin on mac pro 5,1 (GTX 980 TI FLASHED)

[Cuzzupino]

Hi,

I’m new here.

I get a gigabyte gtx 980 ti 6GB OC windforce 3x with bios flashed for EFI.

I want to connect the gpu in the safest way.

I think to connect gpu in this way:

Cable A : dual mini 6 pin to 8 pin
Cable B: dual sata power (from motherboad) to 6 pin and another dual sata power (from optical bay) to another 6 pin, and finally a dual female 6 pin to a single male 8 pin (for a total of 4x sata power to one 8 pin)

In this way i use 4x sata power (2 from optical and 2 from motherboard) and all two mini 6 pin from motherboard. I don’t need other hd...

Do you think that this is a good way to power an hungry gpu?

 

[joot]

I also have a 980 Ti in my flashed 4,1 -> 5,1. I ended up powering my gpu with an external psu...safest method I think...

 

[Dr. Stealth]

I agree... Safest and cleanest way to power hungry GPU's is with an additional PSU.

I put mine in the optical bay and power (2) overclocked 1080 TI's 8+8+8+8 without any issues at all. I can run FurMark for hours without any shutdowns.

https://forums.macrumors.com/thread...us-failed-heres-my-fix.2089578/#post-25534972

 

[Cuzzupino]

I agree... Safest and cleanest way to power hungry GPU's is with an additional PSU.

I put mine in the optical bay and power (2) overclocked 1080 TI's 8+8+8+8 without any issues at all. I can run FurMark for hours without any shutdowns.

https://forums.macrumors.com/thread...us-failed-heres-my-fix.2089578/#post-25534972

View attachment 767473

How can You get the two psu to power at the same time? Can you tell me what to buy?

 

[Dr. Stealth]

I tied the new PSU power to the Mac PSU with only 2 wires. It was very easy to do but if you need instruction maybe you should have a friend do it. The power inputs (120v in my case) just have to be tied together.

 

[iCreate]

I agree... Safest and cleanest way to power hungry GPU's is with an additional PSU.

I put mine in the optical bay and power (2) overclocked 1080 TI's 8+8+8+8 without any issues at all. I can run FurMark for hours without any shutdowns.

https://forums.macrumors.com/thread...us-failed-heres-my-fix.2089578/#post-25534972

View attachment 767473


View attachment 767474

My exact solution, but with blower style GPUs to keep the extra heat from spreading around.
Would be nice if OWC or some other vendor sold an updated power supply for the cMP that already had the cables and capacity for dual GPUs.