Why

Why

Other urls found in this thread:

seagate.com/staticfiles/support/disc/manuals/enterprise/cheetah/15K.7/100516226a.pdf
maritime.org/doc/neets/mod01.pdf
en.wikipedia.org/wiki/Differential_signaling
twitter.com/NSFWRedditVideo

Why what?

>9 pins for current
>8 grounds
>4 data pins

maybe you should look up what serial means and why we don't use 80 pin ata anymore

Yes? What about it? Makes perfect sense.

Not even anything to do with serial specifically, PATA had 40 ground lines with 40 data lines too on a 80 conductor cable.

Why 8 grounds instead of 2?

you want to separate different voltage levels with ground. Same thing with Rx/Tx.

The grounds on the data connector are for shielding, not any actual power transfer.

The 5 grounds on the power connector are needed to spread the current evenly.

Why not just take 12 volts and step it down internally.

To much amp on one rail
Would need more (costier) components on every device instead of just one psu

I don't believe that. There's no way a whatever is in ops pic draws more than 10 watts.

That s hardly any current esp at 12v

For hotswap.

>I don't believe that
No one cares what you believe, go pursue a career on the field and discover the wonderful world of electronics before thinking your opinion matter at all

Hard drives don't even use 3.3V.

Because why convert when you have the voltage you need available?
I'm not even sure SSDs use the 12V at all, but I think on HDDs the 12V was generally used for the motor and maybe the coil.

> There's no way a whatever is in ops pic draws more than 10 watts.
You do realize there are 15k rpm 3.5" disks?

>That s hardly any current esp at 12v
seagate.com/staticfiles/support/disc/manuals/enterprise/cheetah/15K.7/100516226a.pdf

There is 3A drawn from the 12V rail on sequential read operations, pic related

Ok, for the maximum current. All the typical profiles for that drive have it under 10 watts.

And If your psu can't handle 1.5 amps more on 12v without overheating than you done fucked up impossibly bad.

What does the PSU have to do with anything, retard?

Never mind im being super retarded and i know it.

There's more variables blah blah. And no reason to switch when the standard for how pc cpus are designed is fine

There's nothing wrong with it its just more cables

>what are peak spikes

Oh fuck off you were just splitting hairs

>dur I found this one drive that is ober 10 watts

maritime.org/doc/neets/mod01.pdf

Bye.

>Ok, for the maximum current. All the typical profiles for that drive have it under 10 watts.
You're retarded because it clearly says under typical DC
>1.17A 12V
>0.45A 5V
which would be 16.29W

On two rails. My original post is about just having a 12v input and stepping it down inside the drive.


Sup Forums kiddos are the fucking worst. Struggle with theory of mind much????

And it doesn't say that if you actually read the pdf and not just one page fat someone else posted. Here.


Have your gay board

>maximum current ~16.25W
seems to say exactly that.

>Power drops with no UPS
>That's fine I have CoW

>Array spins up
>Forgot to stagger startup
>Trips breaker
>Array dies again

>On two rails. My original post is about just having a 12v input and stepping it down inside the drive.
you'd still have to supply at least 16W, genius

How retarded are you? It clearly says 16 watts.

>My original post is about just having a 12v input and stepping it down inside the drive.
Not the post I replied to. You're just some retard gamer who doesnt understand basic electronics engineering, thinking he knows more than every engineer at every disk company ever. You are the perfect example of the dunning kruger effect.

agreed

>Why not just take 12 volts and step it down internally.

That's the job of the power supply. Considering the fact that all the components inside talk to each other, it's better to have the same reference for each voltage anyway.

Generally, any power conversion generates heat, so it's better to have that in the PSU with its big fan anyway.

Because power management is not the job of a hard drive. It's the job of the power supply.
Yes, some may be required, internally, but the less it does, the better. This means more money invested in producing that device can go into it's ability to perform it's job, versus it's ability to perform a function something else in the system can already do.

Like, I don't get what the complaint is, really, imo. What do we gain from less pins being plugged into a device that would usually use sata, at this point??

I haven't seen anything use 3.3V. They could have gone without it and let us have had slightly slimmer power connectors.

Probably because of backwards compatibility to the 4 pin Molex connectors, which don't provide 3.3V. Many people still use those with an adapter.

The hard disks likely already use 3.3V internally but just have their own low-power (since it's only for logic) regulator.

I have no idea what the fuck i'm talking about - The thread

Connector has 15 pins
Connector is fed by 4 cables, 5 if you count orange.

wouldnt 2 or 3 cables for 12v be enough? only some really old devices use the 5v.

The best answer is usually the simplest.

>why does it have so many grounds
To split the loads

The incessantly asking why is what dumb fucks do. They don't want to know the answer, but rather to see the limits to the poster's answer and then try to use that to justify their illogical original guess.

2.5inch HDDs use 5v only

>HDD claiming 400 IOPS
what sort of DRAM buffer hitting bullishit numbers are these?

>2.5" HDD

Fucking laptops.

en.wikipedia.org/wiki/Differential_signaling

>what sort of DRAM buffer hitting bullishit numbers are these?
Its a 15K RPM disk

even so, what are the conditions for exceeding 200 IOPS? enormous queue depths and service times?

IAMA HDD expert, but it seems like seek rate is generally limited to a number very close to platter rotation time, or 15krpm = 250 Hz. Getting 1.6 IOs per revolution just sounds weird to me.

Every single component has a voltage regulator separate from the PSU. You don't know what the fuck you're talking about.

The first time building a PC with my friend:
> Wait, the little one is for data?