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h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
No!
See the link above!
Two MP SATA ports can provide 40-50 watts in summary!

SATA ports power connector are STANDARD.

3x1.5x12 is the standard.

And many members here do that for a long time already.

So I thought so.
Sloth 75W
6 Pin> 6 Pin 75W
2 Power Sata> 8 Pin 100W
Total 250 W

the way you told me
Sloth 75W
dual mini 6 Pin> 8 Pin 150W
2 Power Sata> 6 Pin 100W ??
Total 325 W ??

and its only using 1 power sata for the 6 Pin?

Your maths doesn’t consider the power draw distribution. The card won’t care how you power the 8pin. As long as it’s rated up to 150W. It may draw 150W from there.

You need to supply power base on the card’s actual power draw or potential draw. But not expect it will draw full 75W from slot, full 75W from 6pin, and only 100W from 8pin.

No one will design a card to do that. Why zero buffer on the slot, zero buffer on the 6pin, but 50W buffer from the 8pin? That’s just what you want, but not how the card programmed to do so.

Unless you actually measured the card’s power draw, and confirm that it will never draw more than 110W from the 8pin. Only using dual SATA to supply 8pin is very high risk to cause damage.
 

Hdalio

macrumors newbie
Jun 5, 2019
21
4
SATA ports power connector are STANDARD.

3x1.5x12 is the standard.

And many members here do that for a long time already.



Your maths doesn’t consider the power draw distribution. The card won’t care how you power the 8pin. As long as it’s rated up to 150W. It may draw 150W from there.

You need to supply power base on the card’s actual power draw or potential draw. But not expect it will draw full 75W from slot, full 75W from 6pin, and only 100W from 8pin.

No one will design a card to do that. Why zero buffer on the slot, zero buffer on the 6pin, but 50W buffer from the 8pin? That’s just what you want, but not how the card programmed to do so.

Unless you actually measured the card’s power draw, and confirm that it will never draw more than 110W from the 8pin. Only using dual SATA to supply 8pin is very high risk to cause damage.


Thank you, I'll do exactly as you told me:
75W Slot
dual mini 6 pin> 8 pin 150W
2 Power Sata> 6-pin W?

Do you have any idea how many W's going to be with the 2 power sata >6 pin?
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Thank you, I'll do exactly as you told me:
75W Slot
dual mini 6 pin> 8 pin 150W
2 Power Sata> 6-pin W?

Do you have any idea how many W's going to be with the 2 power sata >6 pin?

As per standard.

Dual SATA ports provide up to ~110W.

Single 6pin may draw up to 75W.

So, it’s considered enough (or safe).
 

Macschrauber

macrumors 68030
Dec 27, 2015
2,979
1,487
Germany
I would take a dual mini 6 pin to 8 pin

And solder a 6 plus 2 pin to the power supply leads. Outmost is ground, next is 12 Volts positive.

No fiddling with adapters and decent work. Is done in an hour.


image.png
 

Darmok N Jalad

macrumors 603
Sep 26, 2017
5,425
48,333
Tanagra (not really)
Another quality thread. Just as an FYI, I have an MSI RX 580 Armor 8GB OC, which is rated for 185W power consumption, and I managed to get it working with a 6pin to 8 pin cable. My amateur observations with the system plugged into a Kill-a-watt meter suggests the card is pulling 150W more under load than at system idle, so I’m guessing this card is pulling just up to the 185W limit. Loads like Luxmark and Unigine run just fine. Sounds like I may be pushing it a little?
 

tsialex

Contributor
Jun 13, 2016
13,454
13,601
Another quality thread. Just as an FYI, I have an MSI RX 580 Armor 8GB OC, which is rated for 185W power consumption, and I managed to get it working with a 6pin to 8 pin cable. My amateur observations with the system plugged into a Kill-a-watt meter suggests the card is pulling 150W more under load than at system idle, so I’m guessing this card is pulling just up to the 185W limit. Loads like Luxmark and Unigine run just fine. Sounds like I may be pushing it a little?
Yes, you are dangerously near to disarm the PSU. Remember that most cards don't use the full 75W from the PCIe slot, using most of the power needed from the PCIe power connector. People have noticed that the cut-out occurs around 110 to 120W from the PCIe AUX. This over the spec usage will greatly reduce the life of your backplane.
 
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MIKX

macrumors 68000
Dec 16, 2004
1,815
691
Japan
I'm using 2 x Mini 6 pin to 8 PIN male to an EVGA PowerLINK in bridge mode ( not directly connected to the MSI RX 580 8gb ) and then a female 8 pin to male 8 pin . . . to the GPU. this arrangement balances the total power going to the GPU.

( I had to use the PowerLINK in BRIDGE mode because AMD now has the RX 580's 8 pin power socket facing downwards towards the PCB. ) Actually, the arrangement allows a little more of the cMP's intake fan to pass just a little more airflow to the RX 580 8gb.

( NOTE : the other cables are for USB powered fans for the CPU tray area & the two M.2 Samsung 970 & 960 EVO blades)

PowerLink.jpg
 
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Darmok N Jalad

macrumors 603
Sep 26, 2017
5,425
48,333
Tanagra (not really)
Yes, you are dangerously near to disarm the PSU. Remember that most cards don't use the full 75W from the PCIe slot, using most of the power needed from the PCIe power connector. People have noticed that the cut-out occurs around 110 to 120W from the PCIe AUX. This over the spec usage will greatly reduce the life of your backplane.

I'm using 2 x Mini 6 pin to 8 PIN male to an EVGA PowerLINK in bridge mode ( not directly connected to the MSI RX 580 8gb ) and then a female 8 pin to male 8 pin . . . to the GPU. this arrangement balances the total power going to the GPU.

( I had to use the PowerLINK in BRIDGE mode because AMD now has the RX 580's 8 pin power socket facing downwards towards the PCB. ) Actually, the arrangement allows a little more of the cMP's intake fan to pass just a little more airflow to the RX 580 8gb.

( NOTE : the other cables are for USB powered fans for the CPU tray area & the two M.2 Samsung 970 & 960 EVO blades)

View attachment 847551

I just spent the cash on a dual mini 6 to an 8. I have that same MSI RX 580. I really like it quite a bit. I had a Nitro+ RX480 that I was not as happy with in the past. Too loud under load, and the dual BIOS was glitchy.
 

jant09

macrumors newbie
Jul 20, 2019
1
0
Hello,
I have a Mac Pro 5,1 and I want to put a Vega 56 (300w) 2x8pin

So I was wondering how to supply it :

I'm thinking dual 6 pin + 2 sata should works but :

Do I mix 1 sata and 1 mini 6 pin to a 8 pin ? and do it twice
Or 2 mini 6 pin to 8 pin and 2 sata to 8 pin

Can we have one sata + one 6 pin to a 8 pin ? can the Mac Pro handle it ?

thanks
 

tommy chen

macrumors 6502a
Oct 1, 2018
907
390
Hello,
I have a Mac Pro 5,1 and I want to put a Vega 56 (300w) 2x8pin

So I was wondering how to supply it :

I'm thinking dual 6 pin + 2 sata should works but :

Do I mix 1 sata and 1 mini 6 pin to a 8 pin ? and do it twice
Or 2 mini 6 pin to 8 pin and 2 sata to 8 pin

Can we have one sata + one 6 pin to a 8 pin ? can the Mac Pro handle it ?

thanks


much better you will do the pixlas mode
 

h9826790

macrumors P6
Apr 3, 2014
16,656
8,587
Hong Kong
Hello,
I have a Mac Pro 5,1 and I want to put a Vega 56 (300w) 2x8pin

So I was wondering how to supply it :

I'm thinking dual 6 pin + 2 sata should works but :

Do I mix 1 sata and 1 mini 6 pin to a 8 pin ? and do it twice
Or 2 mini 6 pin to 8 pin and 2 sata to 8 pin

Can we have one sata + one 6 pin to a 8 pin ? can the Mac Pro handle it ?

thanks

Vega 56 is NOT a 300W card, it just has dual 8pin.

And none of your plan can feed the card safely if you assume it can draw 150 via each 8pin.

Unless you already measure each 8pin, and make sure both of them won’t draw more than 110W each. You should not pair up a SATA with a mini 6pin.

The lowest output will determine the overall power supply limit of each pair. A SATA only rated up to 55W. So even a mini 6pin is rated up to 75W, and can do 120W in real world. If you pair it up with a SATA, the overall output will be limited to 55W x 2 = 110W, anything beyond this may hit the hard shutdown protection, even worse then just the mini 6pin itself alone.

TBH, it’s easier to go Pixlas mod. Or just use the mini 6pin in this case. If you want SATA power, then should use 3x SATA to single 8pin.
 

Macschrauber

macrumors 68030
Dec 27, 2015
2,979
1,487
Germany
Dont do 2 sata ports, this never delivers 150 Watt.

Dual 6 pin to 8 pin plus Power Supply mod is the only stable way to go
 

adrianc7459

macrumors newbie
Aug 7, 2019
5
0
Hello,

I have a mid-2012 Mac Pro 5,1 with a 2.4 GHz 12 core processor running windows only. I recently purchased an NVIDIA GTX 1070 and I have it connected via a dual mini 6-pin to 8-pin cable. I installed all of the drivers needed and I had the machine boot a couple of times with no shutdowns running GTAV online. I know that the 2 mini-pin connectors on the motherboard can get me a max of 150W, which on the NVIDIA website, my 1070 requires a maximum 150W. For some reason when I boot up my machine, the 2 monitors, even with one connected, does not get a signal. After I shut down and boot it up on a average of 5 or 5 times, it will power the monitors and I can game with no issues. Is this an issue with the GPU not getting enough power to the monitors? It powers my 1070 because the fan comes on when I boot it up and the light is on and I can get the monitors to come on eventually.

I had an XFX RX 480 in it previously, which I used the dual mini 6-pin to 8-pin connector with no issues. That takes 110W to power.

I do have 2 Samsung 860 512GB SSDs in the eSATA ports, 2 out of 4 slots, and a Samsung 970 EVO Plus in the top x4 PCIe slot. My 1070 is in the x16 bottom PCIe slot powering 2 24inch 1080p monitors.

Thanks
 

tommy chen

macrumors 6502a
Oct 1, 2018
907
390
no the connectors on the backplane give you 120W (2 x 60W) stable
all over will burn your backplane someday
 

tommy chen

macrumors 6502a
Oct 1, 2018
907
390
no card, with load resistance
and the PSU shut down at 145W
with 10% headroom it is 130W
absolutly save is 120W
 

adrianc7459

macrumors newbie
Aug 7, 2019
5
0
no card, with load resistance
and the PSU shut down at 145W
with 10% headroom it is 130W
absolutly save is 120W


I think you may be right because i did not have this issue with my RX 480 and my friend has the same machine as me and he is having the same issue with is NVIDIA GTX 560 which is powered with 150W. What do you recommend I do? Pixlas mod?
 

thornslack

macrumors 6502
Nov 16, 2013
410
165
Lots of people say you can “burn out your traces” or “wear out the computer faster” running it at load but I haven’t seen it actually documented.
 
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adrianc7459

macrumors newbie
Aug 7, 2019
5
0
So does anyone know or have experienced their monitors not turning on at bootup during every bootup? I have checked everything, and my only explanation is that most of the time the GPU is not getting enough power to send a signal to the monitors. Every so often it may get enough power to turn them on and that is when I can game and use the GPU. Is there a way to always force a certain amount of wattage to the mini 6 pin ports on the motherboard?
 
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