Current best powered risers available?

[papampi]

Hi guys,

Is it safe to connect molex or 6-pin cable directly to riser board?
As far as I read, the SATA/molex and SATA/6pin power adapters are the ones that should be avoided?

I bought a few riser boards with 6-pin power socket. Came with sata-6pin adapter cables. Should I be using them or try to connect a 6-pin cable directly from the psu 6-pin socket?

Thanks in advance, I also asked the same question in a few thread I posted regarding dual psu and riser boards.

 SATA connectors THEMSELVES are only rated for 54 watts of +12VDC draw, while the PCI-E spec for the bus allows for 75 watts draw.

 MOLEX are rated over 150 watts on the connector, the WIRING is what you have to watch there if you put more than one riser on a chain.

 PCI-E 6-pin using *2* +12VDC lines is good for almost 200 watts, the ones (not actual PCI-E spec) that have 3 +12VDC lines are good for 288.

 Molex and PCI-E 6-pin to riser are safe, SATA is problematic and often UNsafe.

 Keep in mind that the power conversion circuitry on the risers is NOT 100% efficient, so your actual draw from the power connector will be a little MORE than what the card itself is actually pulling.


 The only issue I have with the Mintcell risers to date is that once in a while the USB cable itself is iffy - but they're standard cables and cheap/easy to replace when that happens.

Good info, thanks for sharing

[dcjim1]

Hi guys,

Is it safe to connect molex or 6-pin cable directly to riser board?
As far as I read, the SATA/molex and SATA/6pin power adapters are the ones that should be avoided?

I bought a few riser boards with 6-pin power socket. Came with sata-6pin adapter cables. Should I be using them or try to connect a 6-pin cable directly from the psu 6-pin socket?

Thanks in advance, I also asked the same question in a few thread I posted regarding dual psu and riser boards.

 SATA connectors THEMSELVES are only rated for 54 watts of +12VDC draw, while the PCI-E spec for the bus allows for 75 watts draw.

 MOLEX are rated over 150 watts on the connector, the WIRING is what you have to watch there if you put more than one riser on a chain.

 PCI-E 6-pin using *2* +12VDC lines is good for almost 200 watts, the ones (not actual PCI-E spec) that have 3 +12VDC lines are good for 288.

 Molex and PCI-E 6-pin to riser are safe, SATA is problematic and often UNsafe.

 Keep in mind that the power conversion circuitry on the risers is NOT 100% efficient, so your actual draw from the power connector will be a little MORE than what the card itself is actually pulling.


 The only issue I have with the Mintcell risers to date is that once in a while the USB cable itself is iffy - but they're standard cables and cheap/easy to replace when that happens.

Thank you!

How do you tell PCI-E 6-pin with *2* vs *3* +12VDC, do I count the yellow cables? (the black ones are ground cable?)

I'm in the middle of a getting a single Seasonic 1300W PSU to hopefully power 6 rx580s... anything to watch out for?

[QuintLeo]

How do you tell PCI-E 6-pin with *2* vs *3* +12VDC, do I count the yellow cables? (the black ones are ground cable?)

I'm in the middle of a getting a single Seasonic 1300W PSU to hopefully power 6 rx580s... anything to watch out for?

 It's hard sometimes - but oftentimes one of the leads on the +12VDC side will be brown, other times it'll be smaller gauge, other times there is just no way to tell because they used all the same wires for "economy of scale in purchasing" reasons.

[dcjim1]

How do you tell PCI-E 6-pin with *2* vs *3* +12VDC, do I count the yellow cables? (the black ones are ground cable?)

I'm in the middle of a getting a single Seasonic 1300W PSU to hopefully power 6 rx580s... anything to watch out for?

 It's hard sometimes - but oftentimes one of the leads on the +12VDC side will be brown, other times it'll be smaller gauge, other times there is just no way to tell because they used all the same wires for "economy of scale in purchasing" reasons.

Any recommendation for PCIe power cable length?

The PSU comes with PCIe power cables with one 8pin input and two 6+2pin outputs, but the (6+2)pin outputs are too short apart to plug into riser board. Is it safe to add PCIe extention cords to just one of the (6+2)output end of the pcie power cable?

any maximum recommended length?

thanks in advance...

[gt_addict]

Should be fine. My total length of cables is about 2.5ft. I use extenstions/adapters to go from 6pin to 8pin.

[dcjim1]

Should be fine. My total length of cables is about 2.5ft. I use extenstions/adapters to go from 6pin to 8pin.

With the extension, my total length would get to about 3.5 ft.

I can't find anywhere in the pcie spec that calls for max cable length?

have I missed something?

[QuintLeo]

It's about the wiring, not the PCI-E spec itself.
I don't think they anticipated folks using wiring runs long enough for IIR losses to cause issues, or enough losses to cause noticeable voltage drop to the connector.

[david987]

 The only issue I have with the Mintcell risers to date is that once in a while the USB cable itself is iffy - but they're standard cables and cheap/easy to replace when that happens.

How does one determine the USB cable is iffy? I've had a few problems with Mintcell risers where the rig would freeze/lose GPU connection while mining - I just assumed they were beyond repair and replaced them. What are the signs of bad USB cables?

Also, check this out... Mintcell risers I got last week:
https://i.imgur.com/NIR87IZ.jpg
This one I didn't even try to use

https://i.imgur.com/eKGueEn.jpg
This one boots but makes the rig crash after 15min - 1 hour of mining. Are those capacitors supposed to be perfectly lined up?

[Sledge0001]

I have 4 rigs each running 8 GPU's a piece running these: https://www.amazon.com/gp/product/B074NX9B8V

They work well and I have 0 issues with them

[Swolemine]

I have 4 rigs each running 8 GPU's a piece running these: https://www.amazon.com/gp/product/B074NX9B8V

They work well and I have 0 issues with them

I use these as well. No issues.

[QuintLeo]

 The only issue I have with the Mintcell risers to date is that once in a while the USB cable itself is iffy - but they're standard cables and cheap/easy to replace when that happens.

How does one determine the USB cable is iffy? I've had a few problems with Mintcell risers where the rig would freeze/lose GPU connection while mining - I just assumed they were beyond repair and replaced them. What are the signs of bad USB cables?

Also, check this out... Mintcell risers I got last week:

This one I didn't even try to use

 Swap the cable.
 Trivial to troubleshoot if it's the cable that way.

 Good call on that riser, it's OBVIOUSLY messed up.
 Cap didn't get installed correctly and/or failed.


 The other one I can't say for sure - but it kinda looks like C13 should be there, and not sure if the 2 resistors under the right end of the PCI-E bus connector are needed if you are powering for MOLEX or not (the other regulator "missing" parts are probably for +5VDC supply and not needed with a MOLEX since the PS supplies +5VDC on a MOLEX connector).


 Is the bottom of it "bulged out" so that it CAN'T seat? If so, don't even THINK about trying it - it shorted out or something at some point and seems to be leaking as well.

[david987]

 Is the bottom of it "bulged out" so that it CAN'T seat? If so, don't even THINK about trying it - it shorted out or something at some point and seems to be leaking as well.

The bottom is bulged out yea, as if it burst. I've ordered risers from another brand (https://www.amazon.com/gp/product/B074PS39BK) let's see if I have better luck. I'll try Victony ones next if not.

[dcjim1]

It's about the wiring, not the PCI-E spec itself.
I don't think they anticipated folks using wiring runs long enough for IIR losses to cause issues, or enough losses to cause noticeable voltage drop to the connector.

thanks for the response...

Would using or mixing 16AWG vs 18AWG pcie power cables make a big difference?

I'm using 18AWG cables from the PSU but need to add an extension cable so I can use the same power cable to plug into both the gpu and riser board (6pin), the original psu cable comes with two end points but is only long enough to reach either the gpu or riser but not both. The only extensions I could find right now are 16AWG cables. Any issues that may stem from attaching 16AWG extension cable(connect to riser board) to original 18AWG cable from psu?

[QuintLeo]

It never hurts to use TOO BIG of a wire, except where cost is a factor.

 Runs cooler, less IIR losses (though usually not a BIG difference on those factors for only going "one step" bigger).

[dcjim1]

It never hurts to use TOO BIG of a wire, except where cost is a factor.

 Runs cooler, less IIR losses (though usually not a BIG difference on those factors for only going "one step" bigger).

Cost is certainly a factor ... lol

but I definitely want to be on the safe side.

the more info I dig the more question arise out of them...

It seems to me most of the parts are standard manufacturing, including motherboards, and the only non standard equipments are the riser boards and custom chasis. Any reason why motherboard makers wont release standard x1 - x16 boards that are tested safe to use with PSUs ?

I feel folks would pay a little premium for those parts if they are standardized?

As for chasis/mounting frames, if anyone has a recommendation i'd greatly appreciate it.

I read some debates on wood vs metal, and am somewhat leaning towards metal frames made from iron....

some folks recommend aluminium, but isnt aluminum too good of a conductor to mount electronics on? last I checked, iron is much less conductive?

[QuintLeo]

You don't mount DIRECTLY to the aluminum as such, you use spacers - both MB and riser cards have "isolated" mounting holes so you can get away with using brass or steel spacers.

Iron is close on conductivity to aluminum.
Both are somewhat inferior to copper silver and gold but ALL of them are "conductors" and conduct electricity well.

 Many high-tension power lines back in the past used an iron core with copper electroplated to that core.
 Today the core is usually aluminum due to it being lighter while still being stronger than copper.


 Riser cards ARE fairly standardized - that's why you see so many folks offering the "same version" risers.
 I have no clue who originates the design for each version.

[dcjim1]

You don't mount DIRECTLY to the aluminum as such, you use spacers - both MB and riser cards have "isolated" mounting holes so you can get away with using brass or steel spacers.

Iron is close on conductivity to aluminum.
Both are somewhat inferior to copper silver and gold but ALL of them are "conductors" and conduct electricity well.

 Many high-tension power lines back in the past used an iron core with copper electroplated to that core.
 Today the core is usually aluminum due to it being lighter while still being stronger than copper.


 Riser cards ARE fairly standardized - that's why you see so many folks offering the "same version" risers.
 I have no clue who originates the design for each version.

I got an open frame steel case that mounts everything including the power supply. Everything except for the PSU will be mounted with either spacer or rubber pad (riser boards).

Am I supposed to mount the psu first and ground it? It looks like PSU is the only component that directly touch the steel frame.

[QuintLeo]

The case of the PS is isolated - doesn't matter if you let it ground or not.

[philipma1957]

make sure the risers are isolated from the case.

[koinli]

im using this risers too;

https://www.newegg.ca/Product/Product.aspx?Item=9SIAF6B6KW0303&ignorebbr=1&_ga=2.198289579.52438579.1513916211-662120618.1511639750&_gac=1.159115080.1513117807.CjwKCAiAmb7RBRATEiwA7kS8VB89-cj6yuKOs0-abQ2vnt1LiSmLmR8G3VfTNIhrXEEolq7alAv6MRoCuAMQAvD_BwE