Splitters 6 pin and 8 pin trouble (7 x RTX 3070)

[blackeye_]

Good morning everyone,

first of all after reading some forum threads I have to congratulate with all of you for the great place where to find info online and for the way people interact each other. Then, this is my first thread here so that I think that it's important to make a quick presentation.

I am writing from Italy nearby Rome and I love computer stuff, playing games first person shooter like. I came from the Quake 3 Arena old school community

BTW straight to the point, I have 7 RTX 3070 v1.0 with 3 PSU Corsair RM850 (80 Plus Gold).

https://www.amazon.it/dp/B07S3X7QV7/ref=cm_sw_r_apan_i_74T6E6XWCTFF9XAJD5HB

The cards needs the following power cables:

- one 8-pin (GPU) ;
- one 6-pin (GPU) ;
- one 6-pin (for the Riser);

The problem is that when I use the CORSAIR cable it turns on, when use the splitters it doesn't turn on. Actually this rig is making me crazy, and I always found a solution for this kind or problems but unlikely I am still fighting with it. I need the Y splitter extensions because otherwise the original PSU cables wouldn't reach the farthest gpu mounted on the chassis.

Of course and as a personal mindset I just connected one GPU for the initial tests so that in case of catastrofic power failure or short circuit I still have the rest of GPUs saved.

I hope someone could help me to solve this problem or at least could give me some hint.

Many thanks!

 

[Bigbacon]

what doesn't turn on? the PC, the video card, the riser?

 

[motqalden]

Make sure that both the power and riser power for each gpu is coming from the same psu

 

[blackeye_]

Bigbacon anything turns on, after pushing the Power button I hear a little "click" sounds and nothing happen. Then If I try again pushing the power button another time I don't hear any click sound and the computer doesn't turn on as well.

motqalden I am trying using just one PSU that powers MB, Cpu and one GPU.

If I use the Corsair cables it turns on, instead if I use the extensions it doesn't work..

 

[motqalden]

Sounds like a short. Must be something wrong with the splitters or the way you have it connected if it works without the splitters. Do you have other splitters you can try? Pics of setup?

 

[Bigbacon]

that sounds like the PSU saving itself from destruction. crummy batch of splitters?

 

[legcramp]

You're using a CPU 8-pin to PCIE splitter instead of a PCI-E to PCI-E splitter.

 

[blackeye_]

motqalden I have more splitters from the same supplier, when I tried one couple of splitters I didn't try the remaining one cause I was afraid to "crash" something. I will send some setting's picture during the weekend according to the available free time.

Bigbacon yes..totally, I could have bought a poor product. All the splitters and cables cames from Amazon and Parallel Miner. I did some research before ordering from there, but of course I could have made some wrong setup choices on how and where I connect the extensions. I think that the big picture will be clear when I publish the settings..

legcramp could be.. The last splitter extensions have been purchased from Parallel Miner, these are the splitters I have for the attempts:

1) Short-run 12 inches 16AWG 6 Pin Male to 8 Pin (6+2) Male PCI-e Power Cable for GPU (last bought) ;

https://www.parallelminer.com/produ...-male-to-8-pin-62-male-pcie-power-cable-copy/


2) SilverStone SST-PP07-PCIR - 8pin to PCI-E 6+2pin;

https://www.amazon.it/dp/B00B46XKJW/ref=cm_sw_r_apan_i_RWWZCC1KWKHJXT4MTQW1

3) J&D 2er Pack 6 Pin PCIe Extension;

https://www.amazon.it/dp/B07RW73CB7/ref=cm_sw_r_apan_i_W8WSDV63YGT1EB7PP779

I mean.. I spent a lot of cash trying to catch some valuable products, these are the Risers:

4) BEYIMEI VER 010-X;

https://www.amazon.com/BEYIMEI-Extension-Interface-Ethereum-VER010-X/dp/B08YWVJKQS

I will publish the setting soon so you all can also check the connection with the PSU (where I have some doubts). Btw If you all think something related to the case please do not hesitate to tell me your thoughts or suggestions. Any contribution is appreciated!

 

[Andrew_Carr]

Ok, unless I'm missing something you're using extenders and some different PCIE cables than what your PSU came with and none of what you posted are splitters. Splitters turn 1 thing into 2+ things and look like this.

If you're trying to plug these (https://www.parallelminer.com/produ...-male-to-8-pin-62-male-pcie-power-cable-copy/) directly into your power supply perhaps that's the problem. Do you not have the original cables?

The risers are probably fine.

 

[blackeye_]

Andrew_Carr Exactly, that's correct I am trying to plug different PCIe cable than what my PSU came with. Thank you for the picture!

I have the original cables from Corsair manufacturer but they are short and don't even reach the first GPU mounted on the rig.

Actually the system turns on if I connect the original cables but of course I need extensions.

Regarding the power management and the way I decided to plug everything, considering the following assumptions (MB+CPU+FAN) no more than 250watt and 1 x RTX 3070 Max tdp 220watt, I have chosen to allocate the loads as follow:

1) PSU 850W: 2xRTX3070 + MB + CPU + FAN (690watt);
2) PSU 850W: 3xRTX3070 (660watt);
3) PSU 850W: 2xRTX3070 (440watt);

Total maximun load 1790 watt
Real load during operations should be slightly more than 1000 watt.

The PSU has the depicted plugs in the attached picture. And if I am not wrong I should have tried to plug everything in that way, but I have to double check.

 

[BassTek]

You bought the wrong cables. The ones you bought are for breakout boards that attach to a server style PSU. For your PSU use the original cables and buy splitters. Keep the wattage below 150w per 8 pin cable from the PSU and you should be fine:

 

[blackeye_]

xenium thank you for the suggestion, I never used extenders/splitters and my experience in computer building is very low.... I built just 3 computers in my whole life. Cause of my low experience I made errors but no one is born knowing everythings and the errors are part of the game, this is why I am here... A place where there are people more aware than me.. So thank you very much.

BassTek, I am buying some splitters I will let you know as soon as I have free time to dedicate. Thank you Bass for your time..

Will follow the link of the products:

https://www.amazon.it/dp/B093SNTRX4

 

[Andrew_Carr]

Yeah, those ones look good. Just use only the OEM cables for the direct power supply connections. Apparently some companies even have different wiring depending on the PSU brand, there's no consistency.

 

[Agraffe]

I don’t think it matters whether you are using a 6 pin or 8 pin connector. It’s just a plug and you will be good with anyone out of them.