So I’m looking for a solid answer and only getting a few scarce Tid bits related to 6 gpu builds.
I currently have a 1600 evga g2 with 9 gpu 8 pin ports. However each r9 takes 2* 8 pin connectors. The mobo only needs one cpu connector and I do have an extra available. Yes I know you can’t use that cable because it will fry the gpu, but Silverstone makes a 12v 8 pin EPS to 8 pin pci e adapter. That will still only power 5 total if I’m using two cables per.
So do I buy y splitters or get two PSU s?
If two PSU which combo is best?
a single 1600w will not run 7 Fury’s, I know this because I have them. Buy identical of what you have, and a 2 to 1 spittler on the psu to mobo is your best option
I have 7 1080 Ti’s which consume similar to Fury’s, and I bought x2 HP 1200W 94% platinum PSUs I got on Amazon to feed 6 cards, and a EVGA 500W for one card and processor, and it works great. In case it helps
I was look at some of the 1070 that only took 1 8 pin connector but settled on Furys over the price. Next build I’ll do them, but that does help so thank you both!
Keep the EVGA 1600 and add a HP server 1,500 PSU (eBay = $70, yellow label on top), but you will also need a step-up transformer to take 120v - 220/240v, easy to find on eBay for $100 (5,000 watt rating). Then you need a X-adapter v6 and some cabling, visit Parallelminer for those parts. I had the same cards, 6 of them. The problem with the HP 1,200 is that while it will run on 120v, it is not very efficient and you will notice that the top gets burning hot to the touch. The platinum rated efficiency only applies when you put it on 240v. So just go with the HP 1,500 but add that step-up transformer. Visit Parallelminer to see some pics.
could you tell me how can Sync the PC PSU with the Server PSU?
If I power on or off the PC, how can it sync with the server one??
any harm if I do it manual ???
Could you tel me more in real life daily operation ?
So I’m not an electrical genus but why would not adding an additional 1000w. Or 1300w PSU do the trick?
Sure Mr. Lulu,
Here is how I do it in real life: I press the power button on X-adpater 6 card, that sends power from the HP server 1,500 to four video cards. Then I hit the power on button on my motherboard. The EVGA 1600 PSU is already turned on.
No need for self-test plug or anything else. Works very well for me.
Yes, that was my original setup: one EVGA 1,600 watt and a EVGA 1,300 watt. Thing is, the rig is more stable using the HP 1,500 PSU. Check the manufacturer’s specs to see how efficient your PSU is as the load increases. If electricity is expensive where you live, this matters.
Thanks for reply!
So turn on the server psu before PC PSU right?
How about riser power supply? You use pC one ot server one?
Yes, that’s right: turn on HP PSU server first, then PC PSU/motherboard. Turn off HP server PSU first, then turn off PC PSU/motherboard.
Riser power supply = all from PC Power supply.
HP 1,500 PSU = just 8 pin power to the cards, not the risers, not the motherboard.
Purchase X6 or X7 adapter + cables from Parallelminer - HP 1,500 watt PSU available from Paralleminer or ebay.
Thanks for your detail reply
Being told that PSU cable is not universal standard.
What PCIE cable I can use on the HP PSU??
from google search, many people burn their PSU due to exchange difference model and brand PSU cable…
I just take a look at my Antec Truepower PCIE and HP-1000 PCIE cable seems not same already…
is that any risk for using other brand PCIE cable on that adapter with HP PSU?
I know it have connected X6 / X7 adapter, but do I need order something special PCIE cable for that X6 / X7 adapter???
Could you tell me your practice? thanks
Not sure I understand. I only use the HP 1,500 to supply 8 pin power to the video cards, not to the risers, not to the motherboard. I use the yellow/black 6+2 pin cables sold by parallel miner. They’ve worked fine for R9 Fury and GTX 1070/1080.
Again, the HP PSU does not touch the motherboard, it does not power any PCIe riser boards. Only 8-pin connection to each video card.
I hope that helps. PM me if you want and I’ll send some pictures.
Nestorius, you should not be mixing PSU supply rails for the same loads. 1 PSU powers mobo, peripherals, some GPU’s (power AND riser) to desired wattage. Second PSU powers remaining GPU’s, power AND risers.
Early Pcie risers did not cut the power lines from the Pcie slot and the riser and therefore required you to run them they way that you describe. However, today, POWERED risers provide power from the molex connector and have no power connection to the mobo, only 3.3V data. Therefore, if you power the 8 or 6 pin GPU power from one PSU and the riser from another you are mixing PSU rails in the GPU load. Voltages between PSU’s do not match perfect and there will be differences that will cause current to flow and ground loops.
However, most modern GPU do isolate the 12 volt rail from the main power and the Pcie power so you can usualy get away with this. However, the stories of meted molex connectors and burnt cables are real examples of what can happen if you mix rails between two PSU’s.
so what is the correct connection method for using 2 PSU???
for SAME GPU, Riser and PCIE power should come from same PSU??
let say if you have 6 GPU,
3 GPU + Riser power from A) PSU?
3 GPU + Riser power from B) PSU?
What should be the SAFE connection method??
Seems it is hard to avoid power mixed as you can see,
1 GTX1080ti with riser, it required PCIE 8pins x 2 + PCIE 6 pins x 1 (riser)
Yes, mobo and ALL peripherals from one PSU plus Power AND riser for some GPU’s. Remaining GPU’s, power AND riser from second PSU. All my rigs run this way, and I have three 7 GPU 1080 rigs.
****** Just remember that a 7 GPU 1080 rig requires a 20 amp circuit with 12 gage wire, minimum!!! (Assuming 120V power).
Sorry forgot about the power cable question.
The EVGA PSU’s I use have a video power cable that has both a 8 pin and a 6 pin on the same cable. I’m not a big fan of this since it’s basically a spliter but I’ve not had issues. The alternative is two 1600 PSU’s that can power 8 GPU’s with two cables to each GPU.
**** Below Message which I copy from some serious miner, their practice like Nestorius, for ground issue, seems riser should connect with the PSU which connected to the motherboard board only **
They stated ground issue which is not the same as you said…
But their operation is same as Mr. Nestorius…
I am not professional in electricity… I do want to know the real answer as safety should be on first priority *************
I recently upgraded to a dual power supply setup which had me researching on how to connect them safely.
I came across posts suggesting powering the riser and PCI-E power connector on the card with the same PSU. Others say the psu that powers the motherboard must also power alll the risers. The slave psu should only power the PCI-E power connector on the cards.
Ultimately, I did follow the latter suggestion as it seems logical the same power supply that powers the motherboard should also power the risers connected to the PCI-E slots on the motherboard. The second slave power supply only powers the 6 & 8 pin auxiliary power connector on the video cards. According to another post I came across that connecting the PSU’s that way ensures they share the same ground, which is important.
I also noticed BBT in his latest live stream set up a 9 card dual PSU rig and also explained that when setting it up, you need to power the risers with the same PSU that powers the motherboard and only use the second PSU to power the GPU’s.
After I did some research online, seems your connection method is correct.
all riser should connect to the PSU which connected to the MB.
and second PSU should connect to all GPU 6/8 pins PCIE only.
Thanks for your time and detail answer