SATA II vs USB 3.0 speeds

McGraw · 16 Aug 2014 at 22:38

Hi.

Just did a quick ATTO to see which was the better drive to install lesser used programs to and it seems my 2tb USB 3.0 is about 3 times faster than my 160gb SATA II (150mb/s vs 50mb/s).

Have I just got a slow SATA II drive as I thought they should be similar?

Cheers.

wazza300 · 16 Aug 2014 at 23:09

how full are the drives as that will have an affect

i would have thought the sata2 would be quicker?

McGraw · 16 Aug 2014 at 23:17

USB about half empty and SATA about 2/3 empty.

Same here.

I have an identical SATA drive to test so will see what happens.

wazza300 · 16 Aug 2014 at 23:22

if its a Seagate barracuda 2tb then they are one of the fastest hdd's

depends how fast the other one is but it wont be as quick as the Seagate

not sure what speeds usb3 tops out at either

Surveyor · 16 Aug 2014 at 23:36

SATA 2 and USB 3.0 shouldn't bottleneck any standard HDD.

The SATA 2 interface peaks at ~275MB/s and USB 3.0 at over 400MB/s.

The same HDD should perform equally using either interface as long as they're properly implemented.

McGraw · 17 Aug 2014 at 00:38

USB 3.0 is a 5400 rpm Seagate expansion drive
SATA II is a Maxtor 160gb

McGraw · 17 Aug 2014 at 00:40

Hmm I assumed it was SATA II but no, it's 150 on the label so SATA I?

Surveyor · 17 Aug 2014 at 01:35

150 is SATA I.

It sounds like a pretty old HDD which is why it's so slow.

If you tested the 2TB drive on the SATA II and USB 3.0 interfaces you should get similar speeds.

The only limiting factor should be the speed of the HDD itself.

McGraw · 17 Aug 2014 at 01:56

Thanks.

I'm awaiting a 500gb replacement from a friend so this was only really an experiment.

Interesting though.

KIA · 17 Aug 2014 at 10:48

Surveyor said:
150 is SATA I.

It sounds like a pretty old HDD which is why it's so slow.

This.