MP 1,1-5,1 How to connect a Vega 56 without PSU Mod ?

[Lyndon92]

I'd like to upgrade my Mac Pro 5.1.
I currently have a RX 560 , and i want the strongest GPU without PSU Mod (i don't know how to do the pixlas mod, and i don't feel confident about it ).

I could see the Vega 56 is pretty worth it, especially compared to RX560.
I am wondering idiot question : How to connect it. ? My RX560 doesn't have any connector, just the PCIexpress port .

I found this : https://www.amazon.fr/gp/product/B07F62CHYF/ref=ox_sc_saved_image_1?smid=A2SBSMJWADKVNX&psc=1 (Sorry for french language, but i think you can see what it is ).
If i use this cable, it means i must "sacrifice" 2 sata port to power up the GPU, right ?

I could find this also : https://www.amazon.fr/Broches-Expre...-1-spons&sp_csd=d2lkZ2V0TmFtZT1zcF9hdGY&psc=1

Can i use it to connect to power up the GPU ?

Thanks

 

[velocityg4]

Don't do that. SATA power connectors are not designed to handle that much current. Just because someone makes something. Doesn't mean it is safe. SATA is designed for 54W, 6 pin PCIE is designed for 75W, 8 pin PCIe is designed for 150W. Also those SATA lines are likely on one rail with a total limit of 75W.

 

[Lyndon92]

Sure, i understand.
So, what is the best solution in that case ?

 

[h9826790]

Sure, i understand.
So, what is the best solution in that case ?

For Vega56, connect the GPU in this way should be good enough

How to - downvolt a Radeon VII

Can. However, my recommendation is balancing the demand between the mini 6pins. If you re-read my post #35 again, you should able the see that the power draw via each mini 6pin is very balanced. The reason is because I use a cable combination to balance the demand. "DUAL mini 6pin -> Single...

forums.macrumors.com

 

[Farravi]

I am not a technician nor an engineer and was also not confident about the pixlas mod but plunged in and followed the countless resources that help step by step and successfully upgraded.

It was not the easiest upgrade, if anything it was fidgety and I couldn’t get my hands in certain places but perseverance got me through it. If I did it, so can anyone else.

 

[krakman]

there are several threads on this forum describing in detail how to connect the Vega 56.

just use the "search the forum" function at the top of the page.

1. On vega 56 move the BIOS switch to low power mode
2. buy evga powerlink and use two mini 6pin to 6 pin power cables to deliver power. you do not need mini 6 pin to 8 pin cables but if you have them then use them.
3. make sure you use mavericks or newer OS because it contains the latest drivers. Do not use the older OS because the power efficiency of the drivers is not good.

 

[Lyndon92]

Thank you for your answer, i saw lot of things, a bit confusing because i'm quite a beginner in CMP 5.1 .
How to move the bios switch to low power mode ? Should i use Windows for this, or is there another way from Mac ?

 

[mode11]

Thank you for your answer, i saw lot of things, a bit confusing because i'm quite a beginner in CMP 5.1 .
How to move the bios switch to low power mode ? Should i use Windows for this, or is there another way from Mac ?

There should be a small physical switch on the graphics card itself, likely on one edge. Just slide it to the appropriate position.

 

[Lyndon92]

So i got the Vega 56 today, Sapphire version.
I got tons of issues !

1/ The little switch on the card does not indicate anything, it's just left or right.
2/ I didn't get the EVGA Powerlink today, so i just tried to connect the GPU with the cables.

The fans won't start on the GPU, and i have no display.
Could it because i don't use the EVGA Powerlink ? Or is it because of 6 pins to mini 6 pins ? The GPU has 8 pins.

3/ I don't think the EVGA will fit in the card, my PCI port are ... In the middle of the GPU. I don't think it will fit in.

Too bad

 

[MisterAndrew]

I think the best one without Pixlas mod is RX 6600 XT, as long as you do OpenCore with macOS 12.1+. Don’t do Vega without Pixlas mod.

 

[Lyndon92]

Sure, but i'm not really skilled for that mod. That's why i didn't want to try, too scared to kill my PSU

 

[mode11]

So i got the Vega 56 today, Sapphire version.
I got tons of issues !

1/ The little switch on the card does not indicate anything, it's just left or right.

Move the switch in the direction of the video ports for Quiet (low power) mode:

2/ I didn't get the EVGA Powerlink today, so i just tried to connect the GPU with the cables.

The fans won't start on the GPU, and i have no display.
Could it because i don't use the EVGA Powerlink ? Or is it because of 6 pins to mini 6 pins ? The GPU has 8 pins.

Yes. You're only connecting 6 of the 8 pins on each power socket - it's not surprising the graphics card isn't working properly. You need mini-6-pin to 8-pin cables (or use the PowerLink etc.).

3/ I don't think the EVGA will fit in the card, my PCI port are ... In the middle of the GPU. I don't think it will fit in.

Too bad

It's not an especially elegant solution, but you could mount the PowerLink somewhere convenient, then run cables from it to the GPU.