Whats Faster - Sata 6 vs USB 3.0

[Sharpstick68]

I recently purchased 2x2 TB WD Caviar Green seeing as how best buy was having a sale and amazon also reduced the price, which will most likely go back and forth but I bought them because they are only 119 each. Anyway I plan to use these drives for storage only, now I currently have the same types of drives in a HDD Dock that is USB 3.0, and my motherboard natively supports Sata 6 on all the 5 ports available. My question is what would I be better off doing, putting the 2 drives I have in my dock now inside my computer, putting the new drives I'm getting in the dock, or installing them in my computer?. What is faster in terms of interface is what I'm trying to say...Sata 6 or USB 3.0.

[Ulpian]

SATAIII has 6GBs and USB 3.0 has 5GBs. Also I think that USB has more protocol overhead.

I think that SATA3 is more reliable. Much more.

[TEX4S]

Either way you will get the same results. crap speeds

The connection isnt your bottleneck - its those hard drives.

But to answer your question, the SATA 6Gb connection is currently showing better speeds. I think it has to do with USB3.0 driver maturity.

Both have the ability to get really fast, but right now SATAIII has the edge.

[Sharpstick68]

What's wrong with the hard drives? the interface on it supports sata 3 and 6 so I don't understand.

[Miuku.]

Nothing, you're simply faced with the reality that rotational hard drives are limited by their inherently slow design.

Think of it an an autobahn. The speed limit is 350 but your Toyota can only do 200.

[Sharpstick68]

Uhm, okay?

[spaceelf]

They're right. Hard drives don't hit the max interface speeds.

Native SATA should use less CPU resources though so that's how I'd go.

[Miuku.]

I concur with the above poster - USB always adds unnecessary overhead (especially when copying huge files)

[Guest]

One drive supports USB 3 and the other SATA3. Both of these interfaces support a maximum throughput, but that doesn't mean these drives ever meet that speed.

The only type of hard drives that in fact come even close are SSD's, they work in an entirely different way. I have a couple of fairly fast platter based hard drives and the fastest I've seen out of them via SATA3 is 120MB/s (for large read/writes from a 2nd drive of the same type) which is nothing close to the actual throughput for sata 3, it's actually 0.9375 gigabits.

These drives are connected to SATA 3 but they only have SATA 2 controllers and they don't even hit the max speed for sata 2. My SSD smokes them, it's super fast but even that only has a SATA 2 controller!

So there you have it, don't worry about the interface type at all, look for actual benchmarks for these drives to see how they stack against each other.

[Sharpstick68]

What does that mean when you say USB always adds unnecessary overhead (especially when copying huge files)

[smooth_criminal1990]

SATA-based interfaces also support OS-level Native Command Queueing (NCQ), which decides which orders read/write operations to minimize seeking, in theory making it faster.

[Guest]

BTW, if you're interested in speed, I'd still put my money on sata but you should consider, how many other people have a dockable computer and will you want to transport the data on this drive to share with others at any point? In that case, USB is the obvious choice.

[spaceelf]

What does that mean when you say USB always adds unnecessary overhead (especially when copying huge files)

USB is a host controlled protocol. Very little is typically offloaded at the chipset level. With SATA the chipset controls most of it and the CPU deals with the data as little as possible.

You probably won't usually notice unless you're doing a lot of things at once, with todays CPUs.

[Mando]

youll not see any performance above SATA2 speeds in all honesty with either solution. Physical hard disks are limited by rotational speeds of the platters/mechanical limits. The only way to see perf speeds near SATAIII or USB3 is with SSDs.

the only difference on those drives to previous generations is the interface, nothing has changed internally (or minor things like larger cache) pointless tbvh.

[devHead]

What's wrong with the hard drives? the interface on it supports sata 3 and 6 so I don't understand.

Green hard drives spin at 5400 RPM. So, it doesn't matter whether you have SATA6 connection or USB3, the drive itself is not going to be as fast. There's nothing 'wrong' with the drives per se, but they are slower, and designed primarily for storage, not for speed.

[spaceelf]

2TB ones should still be plenty fast at any speed. (Unless it was one of those weird below 5400 ones, but anyway.)

[Mando]

SATA-based interfaces also support OS-level Native Command Queueing (NCQ), which decides which orders read/write operations to minimize seeking, in theory making it faster.

if the HDD supports it, when connected via USB Win7 will enable NCQ etc on the USB drives also. As long as it detects the drive properly. But your right less overheads using SATA, but in real world it will make next to no difference as the drives themselves wont get past max USB2/SATA2 upper limits anyways, due to mechanical lmitations on the drives.

[moloko]

I do not like how I have to reboot the computer when I connect a SATA drive. USB3 might be slower but much more convenient.

[Guest]

I do not like how I have to reboot the computer when I connect a SATA drive. USB3 might be slower but much more convenient.

If your computer has a SATA dock, you should be able to unplug it whenever you would a USB drive because it should support hot swapping... (I'd check that in your motherboard manual though)

[Jason S. Global Moderator]

SATAIII has 6GBs and USB 3.0 has 5GBs.

sorry, but this misinfo needs to stop. i see it all too often. SATA3 offers 6Gb/s, not 6GB/s. there's a HUGE difference. likewise, USB3 offers a theoretical 5Gb/s, not 5GB/s.

so, OP, USB3 offers a maximum of 625MB/s throughput, but in practice, you'll be lucky to see 350MB/s. That WD Green hard drive is only going to transfer at a maximum of like 80MB/s w/ a large sequential transfer. Write speeds are likely to be even slower.

[Roger H. Veteran]

What's wrong with the hard drives? the interface on it supports sata 3 and 6 so I don't understand.

In a way you can think of it like this - You can buy a new sports car that can reach 240MPH but you are limited to 60MPH because of laws and all that. :D In this case, the road is 6000MPH (Mbps) but the car only maxes out at 150MPH (150MB/s). You can floor it and put in the best gas and tons of stickers (:p) but that wont make it go any faster because it's already at the MAX.

HDDs can only spin so far and push so much data - SSDs on the other hand can reach the magical 550MB/s however.

[Astra.Xtreme]

Internal mounted drives are generally better than external because there is less control throughput. An external dock will have it's own controller which may or may not instruct the drive to "power down" when not in use, among other things, and you won't have much of a choice to override that. If internally mounted, you'll be connected directly to the SATA controller on the motherboard and will have more power control.

Beyond all of this, as others have already said, most of this means nothing since this is a mechanical hard drive we are talking about. And on top of that, it's a Caviar Green, which in my opinion is a terrible terrible drive. They are slow and unreliable, so my advise is to not keep anything on there that will ruin your life if/when the drive dies.

[Japlabot]

The drive still uses an underlying SATA interface regardless of the capabilities of USB3. SATA could be 6Gbps and USB3.0 at 6000Gbps but it is still going to run at 6Gbps because that is what is is really using. USB3.0 is just an extra layer if you don't need it for portability/easy connectivity.

[SirEvan]

Nothing, you're simply faced with the reality that rotational hard drives are limited by their inherently slow design.

Think of it an an autobahn. The speed limit is 350 but your Toyota can only do 200.

there's no speed limit on the autobahn, only sections where there is a recommended speed. you can go as fast as you want in most parts without incident.

[SirEvan]

I do not like how I have to reboot the computer when I connect a SATA drive. USB3 might be slower but much more convenient.

You don't. If you have a hotswap chassis, or cables that support hotswap, you can hot-plug a drive. The difference is that in a hot plug cable, the ground pins stick out further than the 5v and 12v pins, so the ground lines make connection first. Once the drive is grounded, it can have power applied and not have an issue. All my sata 2 drives in my file server can be hot plugged at-will.