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Topic: New White Risers work with BOTH sata AND molex connected at the same time :) (Read 836 times)

legendary
Activity: 1078
Merit: 1011
this is a bit off topic, but seems like a collection of the right guys to ask . .

if I'm powering a 1080 TI and it needs 2x 8 pin + i'm using linux (nvOC 19)

https://www.amazon.com/PCI-Express-Video-Y-Splitter-Adapter-Supply/dp/B00A3OVG4W

can I use this to fill both 8 pin pcie slots with 1 8 pin

each card is only getting 200 watts, and apparently 1 pcie 8 pin can supply 250 watts safely?

Well the actual specification states that a single 8-pin PCIe power connector can deliver up to 150 watts maximum. However, you will probably be getting some power from the actual PCIe slot as well, which can provide up to 75 watts, so yes in your case you should be OK.

You might want to keep an eye on it the first day or so to see if the wires or connector get overly warm, but I still think you would be ok. Most people get in trouble when they try to use those splitters to power multiple cards which then does try to draw way more than 150 watts through the connector causing heat issues and potential fire hazards.
sr. member
Activity: 1414
Merit: 487
YouTube.com/VoskCoin
this is a bit off topic, but seems like a collection of the right guys to ask . .

if I'm powering a 1080 TI and it needs 2x 8 pin + i'm using linux (nvOC 19)

https://www.amazon.com/PCI-Express-Video-Y-Splitter-Adapter-Supply/dp/B00A3OVG4W

can I use this to fill both 8 pin pcie slots with 1 8 pin

each card is only getting 200 watts, and apparently 1 pcie 8 pin can supply 250 watts safely?
legendary
Activity: 1078
Merit: 1011
There are only 3 pins designated for +12VDC (which are pins 13, 14, and 15) so that only makes 3 X 1.5 X 12V = 54 Watts available under maximum load on the 12V rail.

I guess you better read the link I gave you, the new version is 4 pins 12v.

Sorry, I did not see any link to a new SATA power connector pin-out specification, only to a testing methodology pdf that outlines how to test that particular Molex connector. Can you please re-post the link to the new pin assignments in the newer SATA specification? I can only find up to version 3.3 (February 2016) and actually in that one instead of adding a 4th 12VDC line as you imply, they keep it to three and actually reduce the number of 3.3VDC lines by making pin 3 a sense pin.
full member
Activity: 144
Merit: 100
I have some 6 pin PCIE risers that are powered via sata to 6pin cable, and I am thinking of getting 6 pin PICE extensions, so that I can power them from the PCIe cable from the VGA. Is this a good idea, or should I leave it as is?
sr. member
Activity: 2142
Merit: 353
Xtreme Monster
There are only 3 pins designated for +12VDC (which are pins 13, 14, and 15) so that only makes 3 X 1.5 X 12V = 54 Watts available under maximum load on the 12V rail.

I guess you better read the link I gave you, the new version is 4 pins 12v.
hero member
Activity: 756
Merit: 560
yall do realize that sata connecters handle less current than the 4 pin molex, its around 1.5 amps and that's it

You do realize you are wrong and the sata connector spec is 4.5 amps or 54 watts while a molex is 5 amps or 60 watts. They are basically interchangable and both work just fine to power risers. When people are melting stuff ti is 100% their fault for improper setup to begin with.

Also...real world mining tests I have done by using an actual DC amp clamp and some maths.

RX470 pulls 29 watts from the PCIe riser while mining ETH.
RX480 pulls 31 watts from the PCIe riser while mining ETH.
GTX1060 pulls 29 watts from the PCIe riser while mining ETH.
GTX1070 pulls 34 watts from the PCIe riser while mining ETH.

All WELL within sata or molex spec. Just because the theoretical maximum they can pull is 75 watts, in real world tests they do not even come CLOSE.

legendary
Activity: 1078
Merit: 1011
btw heres a link to molex's website for sata crimp terminals and on there spec sheet youll see it says 1.5 amps which equates to NOTHING close to 75 watts on 12v

It's 1.5 amps per pin x 4 = 6 amps x 12 = 72 watts.

Quote
current rating
1. Mount the connector to a test PCB
2. Wire power pins P1, P2, P8 and P9  
    in parallel for power
3. Wire ground pins P4, P5, P6, P10 and  
    P12 in parallel for return
4. Supply 6A total DC current to the power  
pins in parallel, returning from the
parallel ground pins (P4, P5, P6, P10  
and P12)
5. Record temperature rise when thermal
equilibrium is reached

1.5A per pin MINIMUM. The temperature rise above ambient shall not exceed 30 °C at any point in the connector when contact positions are
powered. The ambient condition is still air at 25 °C.


http://www.molex.com/pdm_docs/ps/PS-67490-002.pdf

If it was only 1.5 amps, there would be no reason to develop something that will get burned, everything would fry, reason things get burned are that some stupid miners put 2 gpu's in one connector with spliters, also miners need to pay attention to the temperature and where they put the cables, many stupid miners just put them where the heat from the gpu is coming out, so yes sure it will get burned after a long period, also room temperature is important.

The problem with that assumption is that the test procedure was written to stress the connector to make sure it does not fail, it is not indicative of is normal operation. Case in point, all of the pins they are saying to wire in parallel for power to test with are specified for 3.3VDC and 5VDC lines in production.


Pin      Description
1    +3.3 volts
2    +3.3 volts
3    +3.3 volts
4    ground
5    ground
6    ground
7    +5 volts
8    +5 volts
9    +5 volts
10    ground
11    ground
12    ground
13    +12 volts
14    +12 volts
15    +12 volts


There are only 3 pins designated for +12VDC (which are pins 13, 14, and 15) so that only makes 3 X 1.5 X 12V = 54 Watts available under maximum load on the 12V rail. There are also 3 - 5VDC pins for 22.5 watts and 3- 3.3VDC pins for 15 watts of additional power at those respective voltages. So while one could add all these wattage values up (54+22.5+15) to claim that the SATA connector can provide ~90 watts of power, without the context of associated voltage levels it is meaningless.

Since most of the SATA power adapters for risers that I have seen seem to only include the 12V rails, the actual maximum power ratings for these adapters in my opinion would only be 54 Watts@12V.
sr. member
Activity: 2142
Merit: 353
Xtreme Monster
btw heres a link to molex's website for sata crimp terminals and on there spec sheet youll see it says 1.5 amps which equates to NOTHING close to 75 watts on 12v

It's 1.5 amps per pin x 4 = 6 amps x 12 = 72 watts.

Quote
current rating
1. Mount the connector to a test PCB
2. Wire power pins P1, P2, P8 and P9  
    in parallel for power
3. Wire ground pins P4, P5, P6, P10 and  
    P12 in parallel for return
4. Supply 6A total DC current to the power  
pins in parallel, returning from the
parallel ground pins (P4, P5, P6, P10  
and P12)
5. Record temperature rise when thermal
equilibrium is reached

1.5A per pin MINIMUM. The temperature rise above ambient shall not exceed 30 °C at any point in the connector when contact positions are
powered. The ambient condition is still air at 25 °C.


http://www.molex.com/pdm_docs/ps/PS-67490-002.pdf

If it was only 1.5 amps, there would be no reason to develop something that will get burned, everything would fry, reason things get burned are that some stupid miners put 2 gpu's in one connector with spliters, also miners need to pay attention to the temperature and where they put the cables, many stupid miners just put them where the heat from the gpu is coming out, so yes sure it will get burned after a long period, also room temperature is important.
full member
Activity: 151
Merit: 100
How do you know how the load is distributed? If it's drawing power from multiple connectors simultaneously (which is what you seem to be hoping for in the first line), then that's not really redundancy.

A good question! I ran a test.

With both connections powering the riser, and mining active:
  • Unplug Molex, mining continues...
  • Plug Molex back in
  • Unplug Sata, mining continues...
  • Plug Sata back in
  • Unplug Molex, mining continues...
  • Plug Molex in, Redundancy Check!

Alternate test #1, boot with only SATA connected, while mining:
  • Plug Molex in
  • Unplug Sata, mining continues...
  • Plug Sata back in
  • Unplug Molex, mining continues...
  • Plug Molex back in, Redundancy Check!

Alternate test #2, boot with only MOLEX connected, while mining:
  • Plug Sata in
  • Unplug Molex, mining continues...
  • Plug Molex back in, mining continues
  • Unplug sata, mining continues
  • Plug Sata back in, Redundancy Check!


sr. member
Activity: 462
Merit: 258
Small Time Miner, Rig Builder, Crypto Trader
Based on my experience over the years;

Sata can handle way less than Molex on paper, true (unless you use sata-molex cables), but sata can really handle current above its spec.

The only time I had melted cables is when I plugged 2 x GTX 750 Ti's (60W TDP) that had no aux 6-pin connections on the same molex and/or sata cable (as in, both cables got way too hot). For cards that had 6-pin, it didn't matter, both sata and molex cables were equally, slightly warm.

Simple and safe rule of thumb to follow is to try and only plug one card per sata or molex, 2 at most and you'll be fine after you check the temp of the cables after a few hours of use.

Unless you edit the BIOS and set the PCI link as a primary source of power or increase it beyond 60/72/75 watts or whatever the defulat is you'll be fine because all my nvidia cards prioritized electricity intake from 6/8-pins and I've been mining since Kepler (GTX 6xx series).

your right they can handle a little more, but not 75w that would melt some shit, as you said with 2 gtx 750ti (60w tdp) and no aux connectors on the gpu, if it cant handle 2 of those gpus @ 60w how does Metroid figure 75w is still safe? id give it double what the spec sheet says and that's at best so 3 amps which still doesn't even get close to 75w @ 12v along with 3.3v and 5v. by what you've said even 60w between 2 gpus can melt sata connectors
sr. member
Activity: 336
Merit: 253
Gone phishing...
For those who know, molex and sata risers are typically less reliable than the PCIe ones, due to their lower wattage capability:



Well, how about some redundancy? Below you can see that the new riser has all three connections avail, so I am testing out the riser with both sata AND molex connected at the same time.


How do you know how the load is distributed? If it's drawing power from multiple connectors simultaneously (which is what you seem to be hoping for in the first line), then that's not really redundancy.
legendary
Activity: 2002
Merit: 1051
ICO? Not even once.
Based on my experience over the years;

Sata can handle way less than Molex on paper, true (unless you use sata-molex cables), but sata can really handle current above its spec.

The only time I had melted cables is when I plugged 2 x GTX 750 Ti's (60W TDP) that had no aux 6-pin connections on the same molex and/or sata cable (as in, both cables got way too hot). For cards that had 6-pin, it didn't matter, both sata and molex cables were equally, slightly warm.

Simple and safe rule of thumb to follow is to try and only plug one card per sata or molex, 2 at most and you'll be fine after you check the temp of the cables after a few hours of use.

Unless you edit the BIOS and set the PCI link as a primary source of power or increase it beyond 60/72/75 watts or whatever the defulat is you'll be fine because all my nvidia cards prioritized electricity intake from 6/8-pins and I've been mining since Kepler (GTX 6xx series).
full member
Activity: 151
Merit: 100
An interesting debate has begun!

Now the quality of molex connectors are another matter.

The Molex connector is really good on this one. NOT like the others in the first pic. It goes in smooth Kiss

What is important is that this riser has options! My only concern is that there does not appear to any diodes on-board the riser, as i get voltage on the pins that are NOT being used. Does anyone see any issue with this?
sr. member
Activity: 462
Merit: 258
Small Time Miner, Rig Builder, Crypto Trader
Sata can deliver a lot more than 75 watts, a pcie slot in a motherboard is meant to deliver 75 watts, so sata is good enough for the job. Now the quality of molex connectors are another matter.

yeah lets see some specs on the crimp terminal for sata and lets do some math. cause last I checked hard drive HAS NO USE FOR that much wattage, so why would they over engineer the plug. no consumer grade hard drive uses that much power

btw heres a link to molex's website for sata crimp terminals and on there spec sheet youll see it says 1.5 amps which equates to NOTHING close to 75 watts on 12v

http://www.molex.com/molex/products/datasheet.jsp?part=active/0471281001_CRIMP_TERMINALS.xml
sr. member
Activity: 2142
Merit: 353
Xtreme Monster
Sata can deliver a lot more than 75 watts, a pcie slot in a motherboard is meant to deliver 75 watts, so sata is good enough for the job. Now the quality of molex connectors are another matter.
sr. member
Activity: 462
Merit: 258
Small Time Miner, Rig Builder, Crypto Trader
yall do realize that sata connecters handle less current than the 4 pin molex, its around 1.5 amps and that's it, horrible idea those will infact be unreliable if the gpu decides to pull more than what that cable can handle, I mean come on how stupid yall gotta be, those were NEVER designed for that purpose, it was made for power a danm hard drive that doesn't use much power, btw molex risers are only unreliable if your stupid and power too many risers on the same cable, I have molex powered risers along with pci e powered risers, molex ones been running for months no problems, so honestly to say there unreliable is very inaccurate information
legendary
Activity: 2002
Merit: 1051
ICO? Not even once.
Depends on the balance each connection is taxed.

Also, I rather use mnolex as it's pretty difficulty to find a PSU that can support both the cards and the risers solely through 6/8-pins. And modified server PSUs are a bit of a gamble.
full member
Activity: 151
Merit: 100
For those who know, molex and sata risers are typically less reliable than the PCIe ones:



Well, how about some redundancy? Below you can see that the new riser has all three connections avail, so I am testing out the riser with both sata AND molex connected at the same time.



You can see the white LED is lit when there is power:



1 GPU is running in a x16 slot and one running on the white riser:

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