My 1080Ti comming soon~

[heero503]

Today I prepare some solution and try to share with all of you.
I want to try 2 sata to 6pin and original dual 6 pin to 8pin to drive my new comming 1080Ti... It is PC asus FE edition as I want to work with a 120GT in slot 2 for boot screen.

To do this project, i found if i can use a 2.5" hdd to 3.5" hdd mount to connect the SATA cable. It more firm as i just plug in mac pro stock sata power head beside, I also can do cable management inside.

Finally, fixed all stuff and plug the SATA to 6pin in my 5770 and tested half day.
I have tried run some heavy test that i only see the current in HDD bay 3 is 1.45A and bay4 below 1A or 1.2xA. I believe may be 5770 is not serious then 5870 or comming 1080Ti. I will do more test tomorrow when I received the card Tomorrow. one thing is important ... less cable show out is a must!

 

[Synchro3]

Had a similar idea for another purpose: https://forums.macrumors.com/threads/motherboard-to-pcie-sata-power.1712884/#post-18855446

 

[devon807]

Interested to see how this will come out. I may do something similar but with a 980Ti

 

[Synchro3]

GTX 980 Ti and GTX Titan X (Maxwell) do not need this workaround. Just install a Mini 6 pin to 8 pin power cable and a normal Mini 6 pin to 6 pin cable.

I'm running a GTX Titan X for quiet some time with these cables. Here you go: https://forums.macrumors.com/thread...ible-with-older-macpro.1987000/#post-23224762

Only GTX 1080 Ti needs the SATA power workaround.

 

[heero503]

As I have read all you guy share info and macvidcards, I believe the 8 pin will draw high current than mini 6pin can provide. The most safe method that I use 2x SATA power to drive a 6pin and group the mini 6pins to a 8pin. I started to build the config as above. The HDD mount I bought is WD as I think the electronics part will be more reliable. The SATA connectors are Foxcon! In HK, there is very hard to find and also a good quality cable.

as suggested:
6pin -> 2x SATA (should be 110W limit, but never seen on any official Apple document)
8pin -> 2x mini 6pin (official 150W limit, real world 240W absolute max, operational at 220W max)
PCIe slot (75W).

1080Ti is 250W (21A) max (PCIE 75W (6.25A) + 6->8Pin 150W (12.5A) is already 225W and I think 2x SATA (if safe we get 80% of it max) is 80W 6A enough to handle it~

Only one thing is unknow that how the 6pin share current from 2 SATA port.
I have tested yesterday, she always draw 1.2xA from HDD Bay3 and most the time 0.5xA to 1.2A from Bay 4 when i Connect to 5770 and full load it.

If it is work and stable, I will buy the mini 6pin to 8 pin cable from here to make the cabling easier:
https://www.moddiy.com/products/App...tandard-PCI%2dE-8%2dPin-Video-Card-Cable.html

For dual SATA to 6pin I will search a good quality one, if there is any suggestion, please let me know~

 

[devon807]

GTX 980 Ti and GTX Titan X (Maxwell) do not need this workaround. Just install a Mini 6 pin to 8 pin power cable and a normal Mini 6 pin to 6 pin cable.

I'm running a GTX Titan X for quiet some time with these cables. Here you go: https://forums.macrumors.com/thread...ible-with-older-macpro.1987000/#post-23224762

Only GTX 1080 Ti needs the SATA power workaround.

Ahhh, yes thank you!

 

[heero503]

Actually, it is some different as my old 1080. of course 1080Ti is 30%+ performance than 1080. My main concern is the power setup enough?
I tried Bender benchmark and it is crazy fast in CUDA part... and the current 6pin is mainly from bay 3but bay 4 also share. It normally below 2A but i have seen it will jump to 2.2A each for a very short time. For 6pin to 8pin side, it is mainly on PCIE power Booster B size is keeping in 3.xA.
I also long running Unigine Heaven to see the current change. Unigine Heaven given a great pressure to 1080Ti and all PCIE and 8pin (2x6pin) keep 3.8A, all SATA is over 2A but it is very stable. I run the test and leave for hours, it is still stable, all cable and connect is normal.

I believe it is good if you connect the 2 SATA to prevent power drank issue of 1080 Ti. Tonight I also will get the EVGA power link to addin.

Besides, I found a big problem that I will use native Windows 10 installed in cMP.
I check CPU-Z it only in PCI-E 1.1 and there is some performance drop in windows gaming.
Besides to MVC to flash the EFI, is it no other method to solve this issue?

Actually the cost of send to MVC, USD120 delivery and USD225 flash cost.
USD345 is close to half 1080Ti cost...
I can add some money to build a PC and just swap the 1080 Ti for game..
In MAC side, I can see 1080 Ti is good compare with my broken MVC GTX 680...

 

[fendersrule]

Yes. MVC is rip off.

 

[flowrider]

^^^^And here we go again

Lou