[SOLVED] Dumb question about RGB to SATA

RuffRidersEvo

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May 10, 2014
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Hey guys, i just hooked up RGB to my case and i connected the fans to the same sata cable as my ssd which boots windows, would this cause any issues? Like instanability?
 
Solution
Depend on just how many drives and fans are on the same cable.
According to the SATA specification each pin of the SATA power connector must be rated for a minimum of 1.5 amps. Three pins in parallel are used to carry the +5v current, so the “simple” answer is 4.5 amps.
However, there are only five ground pins, shared between the +3.3v, +5v and +12V supplies. This allows a total return current of 7.5 amps, shared between all three supplies. If the sum of the +3.3v and +12V currents is greater than 3 amps, than the allowable +5V current is reduced accordingly. Obviously, if you are using only +5v, then this restriction does not apply.
Caution is advised! Whenever multiple pins are used to carry a high current, one pin may not make...

Karadjgne

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Depend on just how many drives and fans are on the same cable.
According to the SATA specification each pin of the SATA power connector must be rated for a minimum of 1.5 amps. Three pins in parallel are used to carry the +5v current, so the “simple” answer is 4.5 amps.
However, there are only five ground pins, shared between the +3.3v, +5v and +12V supplies. This allows a total return current of 7.5 amps, shared between all three supplies. If the sum of the +3.3v and +12V currents is greater than 3 amps, than the allowable +5V current is reduced accordingly. Obviously, if you are using only +5v, then this restriction does not apply.
Caution is advised! Whenever multiple pins are used to carry a high current, one pin may not make good connection and cause the other pins to carry more current than they are rated for. Power is still supplied, so there is no clear indication that anything is wrong. But, this will eventually cause overheating and connector failure.

SSDs use @ 1-2W generally, but can pull as much as 10W± on the 5v rail. That's 2A.

Fans use 12v rail and on average pull @ 0.3A ± each. Figure 3 fans = 1A. Add in RGB lighting requirements of @ 2W each, that puts the fan total to 6w± or 0.5A. 3 fans =1.5A.

Shouldnt be an issue. Well below power ratings. Even with 6 fans total including RGB, that'd be 2A on 5v, 3A on 12v, out of a possible 7.5A±.

Still no worries. You'd only ever consider having an issue if the fan motors get burned out and start pulling far more amperage than normal.
 
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