6Gb/s Run's slow!!

up2nogooduk

up2nogooduk

up2nogooduk

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Why is this Western Digital Caviar Black 1TB SATA 6Gb/s 64MB running the same read and wright speed as my Samsung SpinPoint F3? which is only 3Gb/s

I thought it would be higher once connected up to the sata 6Gb/s.

Is there any reason for this ?
It's on a Asus Rampage III Extreme

Cheers :)
 
Yes there's a reason for it.

It's the mechanical HDD which limits the speed not the interface it has.

The best mechanical HDD's will top out at around 140-150MB/s.

The SATA 2 interface goes up to around 280MB/s and SATA 3 around double that.

It doesn't matter which interface the HDD uses as it's not fast enough to saturate either.

I always recommend the F3 over the WD Black for that reason. The same speed at a much lower price.

SATA 3 for HDD's is just a marketing gimmick because people think they're getting a faster drive.
 
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SATA III will give you slightly higher burst speeds (from the cache) but you need SSDs to use it properly.

You will only ever go beyond sustained SATA II speeds with an SSD.

Remember in Raid you use 2 buses so SATA II gives you a max of 600MB/sec and III 1200MB/sec.

I get 1050MB/sec read and 204MB/sec write out of my SSDs in raid0.

Here is an analogy:

Bus speed = ceiling height.
HDD/SSD speed = shelving unit height.
Raid = stacking rooms on top of each other.

So with SATA II my rooms are 2 meters tall, SATA III rooms are 4 meters tall.

Mech HDD shelves are 1 meter tall and have no problem fitting in SATA II rooms, but SSDs are 3 meters tall, they get chopped off in a SATA II room, but you get to fit all of them in a SATA III room.

Having Raid 0 is like stacking rooms on top of each other, but not stacking shelves on each other. By using raid 0 on mech HDDs there is still a large gap between the ceiling and top of the shelf in each room.
 
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up2nogooduk said:
So even with that board, would i get the 500 speeds via SATA 6Gb/s :)
Click to expand...

Probably not.

The SATA 3 ports on that motherboard come from a Marvell 9128 controller which is pretty crap.

With native SATA 3 ports (such as Intel's P67 or Z68) you're looking at potential speeds of over 550MB/s using a fast SSD.

With the Marvell controller you may not see anything much better than the native Intel SATA 2 ports.
 
Meaker said:
SATA III will give you slightly higher burst speeds (from the cache) but you need SSDs to use it properly.

You will only ever go beyond sustained SATA II speeds with an SSD.

Remember in Raid you use 2 buses so SATA II gives you a max of 600MB/sec and III 1200MB/sec.

I get 1050MB/sec read and 204MB/sec write out of my SSDs in raid0.

Here is an analogy:

Bus speed = ceiling height.
HDD/SSD speed = shelving unit height.
Raid = stacking rooms on top of each other.

So with SATA II my rooms are 2 meters tall, SATA III rooms are 4 meters tall.

Mech HDD shelves are 1 meter tall and have no problem fitting in SATA II rooms, but SSDs are 3 meters tall, they get chopped off in a SATA II room, but you get to fit all of them in a SATA III room.

Having Raid 0 is like stacking rooms on top of each other, but not stacking shelves on each other. By using raid 0 on mech HDDs there is still a large gap between the ceiling and top of the shelf in each room.
Click to expand...

I understood it better before you explained it ;)
 
Subliminal Aura said:
Stop faffin around with RAID0 and trying to get high sequential speed which in all fairness is pointless.

Get yourself an SSD with high random read and writes and leave this sordid episode of your life behind.
Click to expand...

If my board had the Intel SATA ports then i think i would, but as Surveyor says, the Marvell 9128 controller are crap :( so i wont get the higher speeds!
 
up2nogooduk said:
Why is this Western Digital Caviar Black 1TB SATA 6Gb/s 64MB running the same read and wright speed as my Samsung SpinPoint F3? which is only 3Gb/s

I thought it would be higher once connected up to the sata 6Gb/s.

Is there any reason for this ?
It's on a Asus Rampage III Extreme

Cheers :)
Click to expand...

OP: Marketing worked on you :p.

A Sata3 mechanical hard drive is a bit pointless really :).
 
up2nogooduk said:
If my board had the Intel SATA ports then i think i would, but as Surveyor says, the Marvell 9128 controller are crap :( so i wont get the higher speeds!
Click to expand...

Well you'd get up to 280MB/s with an SSD on the Intel SATA 2 ports.

The Marvell SATA 3 ports may offer a bit more but nowhere near full SATA 3 speed.
 
up2nogooduk said:
If my board had the Intel SATA ports then i think i would, but as Surveyor says, the Marvell 9128 controller are crap :( so i wont get the higher speeds!
Click to expand...

Point I'm making is that switching to an SSD is like night and day even if you've got a SATA RAID0 setup with 4 mechanicals pushing > 300MB/s you'll find a cheap SSD doing 200MB/s will wipe the floor with it - just saying mate ;)
 
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