Schwarzgerät III

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I chose Sequential Write and Random Read because those are the most intensive operations (barring Spinup) for the 5V and 12V loads, respectively. For the regular use cases, we have no problems: the maximum 5V usage ought be around 64.4W (14 * 0.92A * 5V), and the maximum 12V usage ought be around 107.52W (14 * 0.64A * 12V).

What about spinup, though? We're talking 70.7W of 5V and 339.36W of 12V! That's 24.24W of 12V per disk. A Molex connector can carry 132W of 12V power and 55W of 5V power (11 amps per pin, 1 pin per voltage level). A SATA power connector can carry 54W of 12V power and 22.5W of 5V power (1.5 amps per pin, 3 pins per voltage level). A SATA power connector can thus safely supply spinup current to only two of these Exos drives! With three SATA power connectors from my PSU, that only covers 6 drives, leaving 8 unaccounted for.

What about spinup, though? We're talking 70.7W of 5V and 339.36W of 12V! That's 24.24W of 12V per disk. A Molex connector can carry 132W of 12V power and 55W of 5V power (11 amps per pin, 1 pin per voltage level). A SATA power connector can carry 54W of 12V power and 22.5W of 5V power (1.5 amps per pin, 3 pins per voltage level). A SATA power connector can thus safely supply spinup current to only two of these Exos drives! With three SATA power connectors from my PSU, that only covers 6 drives, leaving 8 unaccounted for. With that said, the three connectors together ought be fine for normal use, following spinup.

...

If I also employed my one Molex, I could handle another two drives, but I need my Molex for a variety of other things. We must then handle this spinup case via another mechanism.

Let's first knock out anything that doesn't need 5V. Our motherboard, CPU, and GPU all take their own cables. The PCIe power cables can carry 75W (6-pin) or 150W (8-pin), almost all of it 12V. Four items in our build require only 12V: the two pumps, the Silverstone fan splitter, and the Monsoon CCFL inverter. Two of these four are in the back, and two in the front. We go ahead and use two of the PCIe cables, together with PCIe-to-Molex PerformancePC adapters and BitFenix Molex splitters, to drive these four items. This takes care of all our fans (save the two on the back of the bays) -- those which weren't on the Silverstone are drawing power from the motherboard.

We have five remaining items requiring 5V power: the flowmeter, the Corsair, and the three front panel USB bays. Of these, two natively want Molex 4-pin, and the other 3 want SATA. Combined with our 14 drives, that's 19 power drains.

...FIXME...

==Externals==

Schwarzgerät III: Difference between revisions

Dank (talk | contribs)

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 I chose Sequential Write and Random Read because those are the most intensive operations (barring Spinup) for the 5V and 12V loads, respectively. For the regular use cases, we have no problems: the maximum 5V usage ought be around 64.4W (14 * 0.92A * 5V), and the maximum 12V usage ought be around 107.52W (14 * 0.64A * 12V).
-What about spinup, though? We're talking <i>70.7W of 5V and 339.36W of 12V</i>! That's 24.24W of 12V <i>per disk</i>. A Molex connector can carry 132W of 12V power and 55W of 5V power (11 amps per pin, 1 pin per voltage level). A SATA power connector can carry 54W of 12V power and 22.5W of 5V power (1.5 amps per pin, 3 pins per voltage level). A SATA power connector can thus safely supply spinup current to only two of these Exos drives! With three SATA power connectors from my PSU, that only covers 6 drives, leaving 8 unaccounted for.
+What about spinup, though? We're talking <i>70.7W of 5V and 339.36W of 12V</i>! That's 24.24W of 12V <i>per disk</i>. A Molex connector can carry 132W of 12V power and 55W of 5V power (11 amps per pin, 1 pin per voltage level). A SATA power connector can carry 54W of 12V power and 22.5W of 5V power (1.5 amps per pin, 3 pins per voltage level). A SATA power connector can thus safely supply spinup current to only two of these Exos drives! With three SATA power connectors from my PSU, that only covers 6 drives, leaving 8 unaccounted for. With that said, the three connectors together ought be fine for normal use, following spinup.
-...
+If I also employed my one Molex, I could handle another two drives, but I need my Molex for a variety of other things. We must then handle this spinup case via another mechanism.
+Let's first knock out anything that doesn't need 5V. Our motherboard, CPU, and GPU all take their own cables. The PCIe power cables can carry 75W (6-pin) or 150W (8-pin), almost all of it 12V. Four items in our build require only 12V: the two pumps, the Silverstone fan splitter, and the Monsoon CCFL inverter. Two of these four are in the back, and two in the front. We go ahead and use two of the PCIe cables, together with PCIe-to-Molex PerformancePC adapters and BitFenix Molex splitters, to drive these four items. This takes care of all our fans (save the two on the back of the bays) -- those which weren't on the Silverstone are drawing power from the motherboard.
+We have five remaining items requiring 5V power: the flowmeter, the Corsair, and the three front panel USB bays. Of these, two natively want Molex 4-pin, and the other 3 want SATA. Combined with our 14 drives, that's 19 power drains.
+<b>...FIXME...</b>
 ==Externals==