What is the max number of drives one can daisy chain off one lead?

D

djgizmo

[H]ard|Gawd
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Dec 24, 2006
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Looking to get a modular psu and just use one lead with a custom cable to power 4 hard drives, 2 optical, and 1 ssd.

Probably will be going with a Seasonic or Antec brand psu as my corsair (non Seasonic) is just a pita.
 
Should be more than enough on the 5V to do that I would think. My Seasonic X-760 only has 3 SATA power connectors per cable. Going to custom splice some?
 
Well you may want to be careful with that much on one lead. I guess the only thing that can go wrong with what you are connecting is your drives may drop out or not be happy due to lack of current. Please post back and let us know how it goes.
 
OMG said:
Well you may want to be careful with that much on one lead. I guess the only thing that can go wrong with what you are connecting is your drives may drop out or not be happy due to lack of current. Please post back and let us know how it goes.
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If hes only connecting one of these to a single lead, he should be fine. That connector even has caps built into it, so even during spinup, I doubt the pull will exceed the amperage of that connector.
 
Well, good news bad news. Invested in a Corsair 750AX (on amazon) and that cable (on amazon as well) but the adapter is wired wrong for me :(
My PSU is mounted on the bottom while that adapter assumes running cables from the top.

Looks like I need someone to make me a custome cable for my 750AX.

Know anyone?
 
well.. theoretically, that would work for the HDD and SSD.. then maybe just get some 3" sata extensions for the ODDs?
 
djgizmo said:
Not even funny.
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I wasn't trying to be funny. If your system has slide in trays for your hard drives, you should be able to just flip them over and then the wire would point down rather then up.

ease up bro
 
Not sure if this helps or not... The maximum you should have on a single molex 4 pin connector (from the PSU) is 18a to 20a. Standard modular cables seem to carry a dual molex split natively, so I surmise that this means ~36a to ~40a.

If someone else could confirm, if it helps.
 
crABtoad said:
Not sure if this helps or not... The maximum you should have on a single molex 4 pin connector (from the PSU) is 18a to 20a. Standard modular cables seem to carry a dual molex split natively, so I surmise that this means ~36a to ~40a.

If someone else could confirm, if it helps.
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Not quite. You can't just double up like that. Even if you split a wire halfway, then the whole current still needs to get through the first bit. AWG18 wire is only rated for 14 amps at best, European equivalent less so. The more you draw, or the longer the cable, the more the voltage drop and heat dissipation. Moreover, drives usually draw most (if not all) from the single 5V wire, so you need to presume that everything is going through that one. The difference with PCI/EPS cables is that those have multiple wires carrying the same voltage to spread the effect of resistance.


To the OP:
Doesn't the AX750 come with several sata cables? You could buy some pop-on sata connectors and cut off some/all of the original connectors.
http://www.frozencpu.com/products/1...tor_-_Black_-_90_M-SCA-16F-BK.html?tl=g51c391
 
WiSK said:
Not quite. You can't just double up like that. Even if you split a wire halfway, then the whole current still needs to get through the first bit. AWG18 wire is only rated for 14 amps at best, European equivalent less so. The more you draw, or the longer the cable, the more the voltage drop and heat dissipation. Moreover, drives usually draw most (if not all) from the single 5V wire, so you need to presume that everything is going through that one. The difference with PCI/EPS cables is that those have multiple wires carrying the same voltage to spread the effect of resistance.
Click to expand...

Oh so, even though there's 2 molex connectors on a standard single PCIE6 power connector (I see them in the included bundles a lot) they're still sharing a single 4 pin molex connector?

You continue to amaze me WiSK.
 
WiSK said:
Not quite. You can't just double up like that. Even if you split a wire halfway, then the whole current still needs to get through the first bit. AWG18 wire is only rated for 14 amps at best, European equivalent less so. The more you draw, or the longer the cable, the more the voltage drop and heat dissipation. Moreover, drives usually draw most (if not all) from the single 5V wire, so you need to presume that everything is going through that one. The difference with PCI/EPS cables is that those have multiple wires carrying the same voltage to spread the effect of resistance.


To the OP:
Doesn't the AX750 come with several sata cables? You could buy some pop-on sata connectors and cut off some/all of the original connectors.
http://www.frozencpu.com/products/1...tor_-_Black_-_90_M-SCA-16F-BK.html?tl=g51c391
Click to expand...

Yes, wisk. It comes with multiple sata power cables. However, I was under the impression that if I ever had to RMA the psu, I had to send the cables as well. Corsair moaned when I didn't and back a fan for an H50.

I'd just make a custom sleeved cable, but no one sells the AX psu connectors (they use different keying than pcie connectors).
 
Im running eight 1TB WD 2.5" drives and several SSDs off one power lead. No issues.
 
thedge said:
Im running eight 1TB WD 2.5" drives and several SSDs off one power lead. No issues.
Click to expand...

My understanding is that most modern sata drives use like 1a to 2a, and it's unrealistic to hit the limit for molex. Actually paying attention to more than just the raw total wattage of a PSU is pretty new to me, so take this with a grain of salt.
 
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