Overclock.net banner

1 - 12 of 12 Posts

·
Registered
Joined
·
2,663 Posts
Discussion Starter #1
HEY OCN

I was looking at the Power specs for SSDs and there next to nothing But why do we still need to have power cables to power them? Im asking this cause Id like to make an external Esata/USB2.0 SSD Because it is very similar price to a Memory stick and Im guessing this would be faster.

So what gives? Are the sata ports on our MOBOs Stingy and Refuse to give ANY POWER AT ALL.
 

·
Premium Member
Joined
·
5,987 Posts
Yup. Most data cables apart from USB and Firewire don't transfer power
 

·
 
Joined
·
29,532 Posts
Quote:


Originally Posted by tagurtoast
View Post

Iknow that But SSDs take next to NO power at all so youd think you could get that off the Sata Data.

The half watt or so that an SSD takes is still more than SATA data cables are designed for. You might see it in the next revision of SATA.
 

·
Registered
Joined
·
590 Posts
Nope, no power. Not to mention the fact that SATA II is a relatively older spec and SSD still aren't very common and mechanical drives require more power. This why almost nothing uses eSATA still. Even most external hard drives that are somewhat portable still sell more USB than eSATA. No one wants to carry a data cable and a power cable for a hard drive.
 

·
Premium Member
Joined
·
4,496 Posts
When SATA was conceived, the concept of drives that required so little power didn't even exist. There are only 7 conductors on a SATA connectors, 4 for data and 3 ground. As this layout is well established and in use today, there are no "unused" pins available for power. Each pin is capable of carrying 1.5A, according to Molex specs, so it would have been possible..
..a
 

·
Premium Member
Joined
·
4,496 Posts
It is very hard when there are no unassigned pins.

If they switched one of the ground pins to +5V power, which would certainly be capable of 7W or so of power, it would be shorted out by every single drive currently in use today.
..a
 

·
Premium Member
Joined
·
5,330 Posts
A better question would be why does eSATA not have any power pins - this would actually make a bit of sense. A wider, combined eSATA data & power connection would be ideal, and could carry the power required to spin up mechanical disks if necessary.

SATA is an internal data connection - why the hell would it need power? You shouldn't be carrying round a bare internal drive anyway, so the fact that it needs 2 cables is irrelevant. Powering internal drives off the motherboard is not a great idea either - you just add to the amount of power you have to put in to the mobo in the first place, and make the board more complicated for no real gain.
 

·
Premium Member
Joined
·
10,490 Posts
Quote:


Originally Posted by jlchavis0844
View Post

Nope, no power. Not to mention the fact that SATA II is a relatively older spec and SSD still aren't very common and mechanical drives require more power. This why almost nothing uses eSATA still. Even most external hard drives that are somewhat portable still sell more USB than eSATA. No one wants to carry a data cable and a power cable for a hard drive.

http://www.performance-pcs.com/catal...ducts_id=25853

Power and eSATA over one connection (plugs into a USB+eSata combo port present on many laptops).
 
1 - 12 of 12 Posts
Top