SATA Transfer Speeds

I

ihmcguinness

Limp Gawd
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Nov 15, 2007
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I've got two WD6400AAKS drives in RAID 1, and another outside of the array. They are all connected via SATA to my P55-UD4P motherboard. I just installed Windows 7 and am transferring data from the third drive into the RAID volume, and windows 7 is reporting a pretty constant speed of roughly 60Mb/s. I thought SATA was supposed to be 3.0Gb/s?
 
3 Gigabit/second is max thorical sata speed.

60 Megabyte/second is what you are getting.

Notice the "bit" and "byte" ending. 1 Byte is 8 bit. When you say Mb (with a small b you say megabit) when you say MB (with a cappital B you say megabyte).
Windows report speed in Megabyte. Sata spec is (and a lot of other) are marketed in "bits" to make it look 8 times more faster and awesome!

60MB/sec * 8 bit = 480Megabit/sec = 0.48Gb/sec (or about 6 times slower than Sata 2)
Everything is normal here. It takes SSD's to reach the end limit of Sata 2, you won't reach it with a mechanical drive.
 
Mechanical harddrives are the limiting factor here, you are barely able to saturate sata let alone getting the max out of sata 2.

a sustained speed of 60mb give or take is decent enough if you are transferring a large amount of data from a single drive.
 
RAID 1 is mirroring so you are unlikely to achieve the best speed a single drive can get.
The AAKS average transfer rate should be above 90MB/s, the same for all 320GB platter 7200rpm drives.
A 33% performance hit, seems quite high.
Check CPU use during drive access to see if that is somehow bottlenecking the controller.
Also compare results from the standalone drive.

You'll have to spend a lot to hit 3Gb/s !
 
60mb on a WD640 seems darn low

what firmware is on those drives, i know some had access time issues and low transfer speeds.


3G is all marketing hype, only now are SSD starting to max out SATA 2 and only in raid set ups.
 
how do you find the firmware? and how would you update it? i tried just copying some videos to the desktop, and it was going like 40mb/s...
 
Get the firmware from your harddrive's manufacturer site. You've got instructions on how to use it.

My suggestion is to use UltraIso to make a usb thumbdrive to flash your hd.
 
Seeing 60MB a sec in a real-world windows file copy seems ok to me. Maybe a tad on the low side, but honestly it's really hard to get better numbers than that, in real-world.
 
Not a bad speed for sustained copy. I wouldn't worry about it.
 
extide said:
Seeing 60MB a sec in a real-world windows file copy seems ok to me. Maybe a tad on the low side, but honestly it's really hard to get better numbers than that, in real-world.
Click to expand...

real world iu have 3 WD 640G drives and i avg around 70-80 on larger file transfers, HDTune and HDtach avg around 90mb
 
MrGuvernment said:
...

3G is all marketing hype, only now are SSD starting to max out SATA 2 and only in raid set ups.
Click to expand...

First of all, a single second gen SSD is already maxing out seq reads at a real world SATA2 limit of 261 MB/s

Second of all, even if SSDs weren't maxing out SATA2, putting them in raid doesn't magically max out SATA2....it would max out the RAID controller, but not SATA2.
 
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