Regarding risers and PSU cables

[nu1mlock]

Hi,

I'm going to order 8 or so risers (will only use 6 GPU's but wanted two extra spares just in case) but I'm not quite sure what to pick. I've also got a question for you experienced miners regarding PSU cables for the risers. So here goes.

Should I order risers with 6-pin connectors? If so, can I power 1 GPU and 1 riser with the same cable from the PSU? If not, then the cables on the PSU won't be enough.

Or should I order risers with molex connectors? If so, can I power two risers with one cable from the PSU? Also, the EVGA G2 1300 that I've purchased only have two cables with molex, would it be possible to take another one from my EVGA G2 750 that I'm not using? I'm assuming it's the same cables. Can I plug the third molex cable (on the PSU side) into one of the ones that are supposed to be for the sata cables (there are only two peripheral slots on the PSU)?

Thank you!

[iamnoobplzhelp]

This is definitely a tricky question.

The riser cards do pull a fair amount of wattage, so you definitely don't want to string a bunch of them on one line. Also the SATA to MOLEX adapters can melt, so I hear. I've never had it happen, but to be safe, try and not use them.

I only put a max of 2 risers on a chain, and less if possible.

I use a mix of the molex powered adapters and the SATA powered adapters like this:
https://www.amazon.com/CHICPICK-Dedicated-Graphics-Extension-Connector/dp/B01NBIOXNQ

I haven't had any problems yet, but like I mentioned, I only do 2 max per chain, 1 if possible.

If you have extra 6-pin, definitely use those, because they are designed to put out more wattage and are less likely to overheat.

[nu1mlock]

The PSU I've purchased has six dedicated cables for the GPU's, so if I can use each cable for one GPU and one riser, then it's all good and I'll go with that.

If that's not recommended, then I'll have to use the molex's but the PSU only has two dedicated molex cables. So with six risers, I'd need an extra molex cable. Question is if I can plug it into the connector in the PSU that's supposed to be for SATA cables - and if I can take that molex cable from another PSU (same model but lower watt)?

[uray]

Hi,

I'm going to order 8 or so risers (will only use 6 GPU's but wanted two extra spares just in case) but I'm not quite sure what to pick. I've also got a question for you experienced miners regarding PSU cables for the risers. So here goes.

Should I order risers with 6-pin connectors? If so, can I power 1 GPU and 1 riser with the same cable from the PSU? If not, then the cables on the PSU won't be enough.

Or should I order risers with molex connectors? If so, can I power two risers with one cable from the PSU? Also, the EVGA G2 1300 that I've purchased only have two cables with molex, would it be possible to take another one from my EVGA G2 750 that I'm not using? I'm assuming it's the same cables. Can I plug the third molex cable (on the PSU side) into one of the ones that are supposed to be for the sata cables (there are only two peripheral slots on the PSU)?

Thank you!

most PSU these days have limited molex connector, and have a tons of sata connector
and most sata cable will be burned out to flame on RX GPU, so there are no place for sata in mining rig to be safe
since pcie 6-pin cables are limited, and even more limited molex, it still better to use pcie 6 pin cables since their spec is designed to deliver up to 150w (molex is only 50w, sata is only 35w)

so the solution is just use PCIE 6-pin splitter, one end for riser, and another one for gpu, so each gpu+riser only use one cable from PSU

[stef_stef]

Hi,

I'm going to order 8 or so risers (will only use 6 GPU's but wanted two extra spares just in case) but I'm not quite sure what to pick. I've also got a question for you experienced miners regarding PSU cables for the risers. So here goes.

Should I order risers with 6-pin connectors? If so, can I power 1 GPU and 1 riser with the same cable from the PSU? If not, then the cables on the PSU won't be enough.

Or should I order risers with molex connectors? If so, can I power two risers with one cable from the PSU? Also, the EVGA G2 1300 that I've purchased only have two cables with molex, would it be possible to take another one from my EVGA G2 750 that I'm not using? I'm assuming it's the same cables. Can I plug the third molex cable (on the PSU side) into one of the ones that are supposed to be for the sata cables (there are only two peripheral slots on the PSU)?

Thank you!

most PSU these days have limited molex connector, and have a tons of sata connector
and most sata cable will be burned out to flame on RX GPU, so there are no place for sata in mining rig to be safe
since pcie 6-pin cables are limited, and even more limited molex, it still better to use pcie 6 pin cables since their spec is designed to deliver up to 150w (molex is only 50w, sata is only 35w)

so the solution is just use PCIE 6-pin splitter, one end for riser, and another one for gpu, so each gpu+riser only use one cable from PSU

Is this the cable?

http://www.ebay.com/itm/18AWG-6-pin-to-2x-6-2-pin-6-pin-8-pin-Power-Splitter-Cable-PCIE-PCI-Express-/361651807884?hash=item543420a68c:g:eEYAAOSw0fhXjlMJ

[uray]

The PSU I've purchased has six dedicated cables for the GPU's, so if I can use each cable for one GPU and one riser, then it's all good and I'll go with that.

If that's not recommended, then I'll have to use the molex's but the PSU only has two dedicated molex cables. So with six risers, I'd need an extra molex cable. Question is if I can plug it into the connector in the PSU that's supposed to be for SATA cables - and if I can take that molex cable from another PSU (same model but lower watt)?

if you want to use multiple PSU,, you shouldn't mix 1 PSU for riser and another for GPU.

GPU+Riser should be powered by same PSU, as there are electrical power connection between PCIE power socket on GPU and PCIE slot in Riser.
Power connector on riser is not to power up riser, it is to power up gpu via pcie-slot 1x connector which spec is allow gpu to take up to 72w from these pcie 1x slot, so sata powered riser is should not be allowed

splitting multiple psu between gpu and mothherboard is fine, splitting multiple psu between (gpu+riser) and another (gpu+riser) is fine too

[uray]

Hi,

I'm going to order 8 or so risers (will only use 6 GPU's but wanted two extra spares just in case) but I'm not quite sure what to pick. I've also got a question for you experienced miners regarding PSU cables for the risers. So here goes.

Should I order risers with 6-pin connectors? If so, can I power 1 GPU and 1 riser with the same cable from the PSU? If not, then the cables on the PSU won't be enough.

Or should I order risers with molex connectors? If so, can I power two risers with one cable from the PSU? Also, the EVGA G2 1300 that I've purchased only have two cables with molex, would it be possible to take another one from my EVGA G2 750 that I'm not using? I'm assuming it's the same cables. Can I plug the third molex cable (on the PSU side) into one of the ones that are supposed to be for the sata cables (there are only two peripheral slots on the PSU)?

Thank you!

most PSU these days have limited molex connector, and have a tons of sata connector
and most sata cable will be burned out to flame on RX GPU, so there are no place for sata in mining rig to be safe
since pcie 6-pin cables are limited, and even more limited molex, it still better to use pcie 6 pin cables since their spec is designed to deliver up to 150w (molex is only 50w, sata is only 35w)

so the solution is just use PCIE 6-pin splitter, one end for riser, and another one for gpu, so each gpu+riser only use one cable from PSU

Is this the cable?

http://www.ebay.com/itm/18AWG-6-pin-to-2x-6-2-pin-6-pin-8-pin-Power-Splitter-Cable-PCIE-PCI-Express-/361651807884?hash=item543420a68c:g:eEYAAOSw0fhXjlMJ

yup that it is, only use pcie splitter that use at least 18 awg wire, 16 awg is better, but never use 20 or 24awg wire

[Cereberus]

A fully modular PSU like Corsair RM1000i comes directly with 8 PCIE cables that can be made 6 or 8 pin and it can support up to 8 GPU-s , it also come with 12 Sata cable connectors enough to power up many risers. I think the PSU is the most delicate part choosing when building a mining rig. This PSU supports easily up to 6 cards of RX 480,tested by me as one card max power draw I see in GPU-z latest version is 133 watt.

http://www.corsair.com/en-gb/rmi-series-rm1000i-1000-watt-80-plus-gold-certified-fully-modular-psu

[uray]

A fully modular PSU like Corsair RM1000i comes directly with 8 PCIE cables that can be made 6 or 8 pin and it can support up to 8 GPU-s , it also come with 12 Sata cable connectors enough to power up many risers. I think the PSU is the most delicate part choosing when building a mining rig. This PSU supports easily up to 6 cards of RX 480,tested by me as one card max power draw I see in GPU-z latest version is 133 watt.

RX480 is powered by 6-pin pcie power not 8-pin so it definitely take up to 75w from the connector (since 6-pin pcie is max 75w, 25w for each pin), if the gpu take 133w then there are 133-75 = 58w gpu take from PCIE slot 1X, i am sure it is only for peak consumption of short period of time, it its continuously like this then sata power connector will be burn because sata only limited to 35w power delivery

so never use any sata power for gpu mining

[Cereberus]

A fully modular PSU like Corsair RM1000i comes directly with 8 PCIE cables that can be made 6 or 8 pin and it can support up to 8 GPU-s , it also come with 12 Sata cable connectors enough to power up many risers. I think the PSU is the most delicate part choosing when building a mining rig. This PSU supports easily up to 6 cards of RX 480,tested by me as one card max power draw I see in GPU-z latest version is 133 watt.

RX480 is powered by 6-pin pcie power not 8-pin so it definitely take up to 75w from the connector (since 6-pin pcie is max 75w, 25w for each pin), if the gpu take 133w then there are 133-75 = 58w gpu take from PCIE slot 1X, i am sure it is only for peak consumption of short period of time, it its continuously like this then sata power connector will be burn because sata only limited to 35w power delivery

so never use any sata power for gpu mining

RX 480 is powered up by 8-pin pcie power and not 6-pin, I have it right in front of me so I am not wrong. The sata is only connected to the riser from the PSU and the card also get's power from the PSU via the 8-pin pcie cable. I have those running from a few weeks and I don't see any problem until now.

[nu1mlock]

if you want to use multiple PSU,, you shouldn't mix 1 PSU for riser and another for GPU.

GPU+Riser should be powered by same PSU, as there are electrical power connection between PCIE power socket on GPU and PCIE slot in Riser.
Power connector on riser is not to power up riser, it is to power up gpu via pcie-slot 1x connector which spec is allow gpu to take up to 72w from these pcie 1x slot, so sata powered riser is should not be allowed

splitting multiple psu between gpu and mothherboard is fine, splitting multiple psu between (gpu+riser) and another (gpu+riser) is fine too

Sorry if I wasn't clear with my message. I'll try to explain what I meant better.

The EVGA G2 1300 that I've purchased is modular and has two inputs for molex cables. Which means I could maybe run two risers per cable for a total of four risers.

However, the PSU also has inputs that are meant for SATA cables. The connector looks the same. Could I take one of the molex cables that came with my other EVGA G2 750 that I don't use and plug it into one of the SATA connectors on the 1300 PSU?

If you look at this image it might be clearer what I mean. The molex connectors are the ones called "PERF1" and "PERF2". To the left of those there are four connectors for SATA cables. Could I use another molex cable and plug it in to the SATA connectors instead?

https://www.evga.com/products/images/gallery/120-G2-1300-XR_XL_5.jpg

[uray]

if you want to use multiple PSU,, you shouldn't mix 1 PSU for riser and another for GPU.

GPU+Riser should be powered by same PSU, as there are electrical power connection between PCIE power socket on GPU and PCIE slot in Riser.
Power connector on riser is not to power up riser, it is to power up gpu via pcie-slot 1x connector which spec is allow gpu to take up to 72w from these pcie 1x slot, so sata powered riser is should not be allowed

splitting multiple psu between gpu and mothherboard is fine, splitting multiple psu between (gpu+riser) and another (gpu+riser) is fine too

Sorry if I wasn't clear with my message. I'll try to explain what I meant better.

The EVGA G2 1300 that I've purchased is modular and has two inputs for molex cables. Which means I could maybe run two risers per cable for a total of four risers.

However, the PSU also has inputs that are meant for SATA cables. The connector looks the same. Could I take one of the molex cables that came with my other EVGA G2 750 that I don't use and plug it into one of the SATA connectors on the 1300 PSU?

If you look at this image it might be clearer what I mean. The molex connectors are the ones called "PERF1" and "PERF2". To the left of those there are six connectors for SATA cables. Could I use another molex cable and plug it in to the SATA connectors instead?

https://www.evga.com/products/images/gallery/120-G2-1300-XR_XL_5.jpg

yes you can, personally i have EVGA GQ series exactly like that, and done cable test using multimeter
if G2 and GQ are same then you can put sata/molex to that connector like i did, but i never had G2

[Cereberus]

@Uray

I just checked to make sure if it some overheating was happening as after reading what you told me I just got to check the cards on the riser. Normal heat, just like the one in the motherboard. Sata 4 pin cable is ok  too. I hope I will not burn anything by keeping this configuration but I have seen many mining videos on youtube that are on this exact configuration as mine.

[nu1mlock]

yes you can, personally i have EVGA GQ series exactly like that, and done cable test using multimeter
if G2 and GQ are same then you can put sata/molex to that connector like i did, but i never had G2

That's great news if it's possible!

This also means that I should buy risers with molex connectors, I assume? That way I don't need to buy extra 6-pin splitters. Or is 6-pin splitters and use them still better than using molex cables?

Edit: I should mention that I've purchased six Sappphire RX 570 Pulse Mini. According to Sapphire they're drawing less than 150W. If the 6-pin cable is rated for 150W then molex with another 50W should be more than enough for those GPU's, correct?

[forkbomb]

most PSU these days have limited molex connector, and have a tons of sata connector
and most sata cable will be burned out to flame on RX GPU, so there are no place for sata in mining rig to be safe
since pcie 6-pin cables are limited, and even more limited molex, it still better to use pcie 6 pin cables since their spec is designed to deliver up to 150w (molex is only 50w, sata is only 35w)

so the solution is just use PCIE 6-pin splitter, one end for riser, and another one for gpu, so each gpu+riser only use one cable from PSU

Hi all,
sorry for the silly wuestion, but of course I lack in knowledge of hardware, since I can't understand this point.
You said that every card+raiser need power supply, and you use PCIE 6-pin splitter for every card, so you have a total of 6 PCIE 6-pin cables. But if the connectors are only 2 in the PSU (in the picture OP posted I presume they are perif1 and 2, as he said), how do you connect them?
I know it is a dumb question, but I can't figure it out.
Thanks

[nu1mlock]

Hi all,
sorry for the silly wuestion, but of course I lack in knowledge of hardware, since I can't understand this point.
You said that every card+raiser need power supply, and you use PCIE 6-pin splitter for every card, so you have a total of 6 PCIE 6-pin cables. But if the connectors are only 2 in the PSU (in the picture OP posted I presume they are perif1 and 2, as he said), how do you connect them?
I know it is a dumb question, but I can't figure it out.
Thanks

The molex cables are connected to the "PERIF1" and "PERIF2". It looks like 6-pins on the PSU but the other end of the "PERIF1" and "PERIF2" are molex cables.

The 6-pin cables that we're talking about are the ones that are used on GPU's. On the PSU they are connected to the ones on the right (the VGA1-6). So there are 6x 6-pin cables. Molex cables, however, only have two connectors on the PSU (the "PERIF1" and "PERIF2").

He was talking about splitting those 6 cables to make them 12 in order to use them for both the GPU's and risers.

I hope that makes more sense.

[uray]

yes you can, personally i have EVGA GQ series exactly like that, and done cable test using multimeter
if G2 and GQ are same then you can put sata/molex to that connector like i did, but i never had G2

That's great news if it's possible!

This also means that I should buy risers with molex connectors, I assume? That way I don't need to buy extra 6-pin splitters. Or is 6-pin splitters and use them still better than using molex cables?

one dedicated molex cable for one riser is safe, but never use single cable for multiple riser in daisy chain

but personally i prefer to use 6-pin powered riser, not just because its safer, but molex powered riser are using 1x 12v (yellow) and 1x 5v (red) rail.
while pcie riser use 3x 12v (yellow) rail
most psu has limited 5v rail wattage, but huge 12v wattage (and mostly psu watt spec are for 12v rail, so 1000w psu means 1000w for 12v rail). if you ran out of 5v watt limit it could be problematic

GPU use 12v and 5v to power up, most 12v are taken from GPU power connector, and 5v (and some tiny 12v) are taken from PCIE-1X slot
on PCIE 6-pin powered riser it mising 5v pin, they convert 12v to 5v by using step down converter, highlighted in red box, so these riser only take 12v and convert some into 5v, so it does not use 5v rail from PSU, while Molex riser directly use 12v and 5v from PSU without any conversion

Edit: I should mention that I've purchased six Sappphire RX 570 Pulse Mini. According to Sapphire they're drawing less than 150W. If the 6-pin cable is rated for 150W then molex with another 50W should be more than enough for those GPU's, correct?

6-pin cable rated for 150w is actually not accurate, the story is initial pcie power cable is only 6-pin they rated it for 75w, but there's need to deliver more than 75w, so they changed the spec, pcie power should be rated 150w, to differentiate which cable can deliver 75w (older spec) or 150w they add 8-pin connector, which another 2 pin is not to deliver power, but only to signal GPU if these another 2 cables is connected it means the cable is on newer spec (150w), gpu can take up to 150w, but if only 6 pins are connected gpu only allowed to take 75w since the cable is assumed on older spec which is rated 75w

both 75w and 150w connector deliver power through 3x 12v pins, so it doesn't matter 6-pin or 8-pin connector since both are using 3 pin to deliver power, what matter is the diameter of cable (which is rated in awg), 18-16 awg wire can be configured for 6-pin, 6+2pin or 8 pin, but 24-20awg only allowed to be configured as 6-pin, since 24 awg wire each can't deliver more than 25w of power

most current PSU cable are using 18awg or 16awg, so it is safe to assume it can deliver up to 150w for 6-pin/8-pin connector

now about that 570 pulse mini, if the gpu use 6-pin connector, then the gpu will only take 75w from gpu power connector, so if i assume that "less than 150w" words are meant to be "it never exceed 150w, but it can take up to 150w" then when it take 150w, gpu will take 75w from 6-pin connector on gpu, and another 75w from the riser, since molex are rated 50w, its an overcurrent for molex connector

[iamnoobplzhelp]

The PSU I've purchased has six dedicated cables for the GPU's, so if I can use each cable for one GPU and one riser, then it's all good and I'll go with that.

If that's not recommended, then I'll have to use the molex's but the PSU only has two dedicated molex cables. So with six risers, I'd need an extra molex cable. Question is if I can plug it into the connector in the PSU that's supposed to be for SATA cables - and if I can take that molex cable from another PSU (same model but lower watt)?

if you want to use multiple PSU,, you shouldn't mix 1 PSU for riser and another for GPU.

GPU+Riser should be powered by same PSU, as there are electrical power connection between PCIE power socket on GPU and PCIE slot in Riser.
Power connector on riser is not to power up riser, it is to power up gpu via pcie-slot 1x connector which spec is allow gpu to take up to 72w from these pcie 1x slot, so sata powered riser is should not be allowed

splitting multiple psu between gpu and mothherboard is fine, splitting multiple psu between (gpu+riser) and another (gpu+riser) is fine too

I have been using one PSU to power the risers and one PSU to power the GPU for all my mining machines. Never had a problem.
I use one of these to power the cards:
https://www.newegg.com/Product/Product.aspx?Item=9SIA7GT5NK5071

And then a 600-700w to power the motherboard, SSD, and risers. Would that normally cause a problem?

[uray]

The PSU I've purchased has six dedicated cables for the GPU's, so if I can use each cable for one GPU and one riser, then it's all good and I'll go with that.

If that's not recommended, then I'll have to use the molex's but the PSU only has two dedicated molex cables. So with six risers, I'd need an extra molex cable. Question is if I can plug it into the connector in the PSU that's supposed to be for SATA cables - and if I can take that molex cable from another PSU (same model but lower watt)?

if you want to use multiple PSU,, you shouldn't mix 1 PSU for riser and another for GPU.

GPU+Riser should be powered by same PSU, as there are electrical power connection between PCIE power socket on GPU and PCIE slot in Riser.
Power connector on riser is not to power up riser, it is to power up gpu via pcie-slot 1x connector which spec is allow gpu to take up to 72w from these pcie 1x slot, so sata powered riser is should not be allowed

splitting multiple psu between gpu and mothherboard is fine, splitting multiple psu between (gpu+riser) and another (gpu+riser) is fine too

I have been using one PSU to power the risers and one PSU to power the GPU for all my mining machines. Never had a problem.
I use one of these to power the cards:
https://www.newegg.com/Product/Product.aspx?Item=9SIA7GT5NK5071

And then a 600-700w to power the motherboard, SSD, and risers. Would that normally cause a problem?

on most case it wont be a problem, as long as both PSU are connected to same ground wire, since both PSU ground ended up on the same home power plug it will be on the same earth ground, but on some case, there are different circuitry between two kind of PSU which make their ground is not equal or some other cause, then some problem

[iamnoobplzhelp]

Thanks for clarification. What if I use a power cable joiner? Will that help with the single ground?

Currently both PSUs are plugged into the same surge protector.

Eventually they will be on the same PDU once I get that installed.