SATA II but only getting 168MB/s?!

mcwildcard

mcwildcard

mcwildcard

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In my quest for a faster running system I found out that the OEM HDD I bought off a mate for storage is actually a WD2500KS SATA-II 16MB cache, bit of a bonus, I had no idea!
So anyway, I've checked the jumper and it's been removed, but HDTach shows a burst speed of only 168MB/s :(
I have a 965P-DS3 mobo, which I believe supports SATA-II, so I'm a bit stumped as to why it's basically running at normal SATA speed?!?
Would it make a difference that the drive has been partitioned?
Is there anything I might need to change in the BIOS?

Any help would be greatly appreciated, I know nuffink!!

 
Could be a number of things - poor controller, controller tied to the PCI bus (for those who say that the limit is 133MB/s, yes I know, but sometimes HDTach can read bursts incorrectly), etc.

More to the point - ignore burst speeds. They mean virtually nothing. You will never, ever be able to tell the difference between 150MB/s and 300MB/s burst. Sustained read and access times are the important stats and yours are pretty much spot on for that drive.
 
It should have a sustained read of about 10MB/s more that you current have due to the perpendicular tech and higher density platters. I have 4 of them and can safely say yes, they are better. How much so, difficult but they are one of the best 7200rpm drives you can get.
 
My mates Hitachi 320GB 16MB is 8mb/sec avg rate fast than my 250 is. So looks like the bigger capacity seems to make a difference. Will let you know later on next week when i get my 500GB SE16.

Oh and here's the same drive in my main rig which is also a DS3


The avg speed is basically the same again but the burst is a little higher.
 
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elfy said:
i'm guessing it's the data density on the platters that helps
Click to expand...
It's a new recording method on the new drives, so it's more than just areal density and is effectively the whole system.

The 250GB is just as good. All the 7200.10 drives use the same platters - 188GB I believe.
 
smids said:
The 250GB is just as good. All the 7200.10 drives use the same platters - 188GB I believe.
Click to expand...
that's one thing i've never understood

188GB/platter, 250GB capcaity? so 2 platters. does this mean there's 116GB sitting there that we can't access?
 
elfy said:
that's one thing i've never understood

188GB/platter, 250GB capcaity? so 2 platters. does this mean there's 116GB sitting there that we can't access?
Click to expand...
In effect.
 
Most of that "space" doesn't exist, to get 250Gb from 188Gb platters you use 3 sides of two platters so there's 282Gb of magnetic material available (and only 3 heads). The drive is then short stroked to limit access to part of the platters to give the 250Gb capacity.
 
rpstewart said:
Most of that "space" doesn't exist, to get 250Gb from 188Gb platters you use 3 sides of two platters so there's 282Gb of magnetic material available (and only 3 heads). The drive is then short stroked to limit access to part of the platters to give the 250Gb capacity.
Click to expand...
...there is also a small amount of the 'spare' used to cover for any bad blocks which may develop. The hard drive will mark these as bad and use some of the reserved space to retain the capacity.

It's far more costly to make different capacity platters than to simply use the same and limit it.

http://www.ntfs.com/hard-disk-basics.htm for a good read.
 
That's not bad at all actually. Modern hard drives can only read at about that speed anyway. It's one of the reasons why SATA300 (no such thing as SATA2!) offers virtually no improvement over SATA150 unless you start using RAID. About the only time the extra speed can come in useful are from busts of data from the drive's cache. Other than that, you're limited by the speed of the drive and that's still well below even 150MB/s.
 
nc11 said:
This is really slow. Do you have a SATA2 capable mobo?
Click to expand...
80MB/sec at beginning of drive, is about right for that drive, if you're referring to the burst speed, it's meaningless so I don't see why it matters.
 
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while burst speed isnt everything, it must make some difference. heres my hdtach for 2 of my drives running on the sataII

 
I've just completed the defrag on my new Seagate 7200.10 500GB drive. It replaces the same model, albeit 400GB version, which failed completely today.

I have taken the jumper out this time to allow for SATA300 interface and I have to say that the improvement is quite obvious.

Have tried the HDtach app but it's not compatible with vista. Does anyone have a different tool that will benchmark the drive speed?
 
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