Why is does this hard drive have slow access times?

I've got a Seagate 160gb (ST9160301AS) hard drive that has a good SMART report - no bad sectors, no crc errors, etc. And it has a respectable 50MB/s throughput, over a nice smooth curve. But it's access times are really bad, at 26+ ms. I've chkdsk /r'd it, defragged and optimized it, but its performance remains abysmal. Is there anything I can do for it?

Goto gparted.org, download/create a bootable version.
In gparted create a new partition tabel, create a new ntfs partition and try your acces time's again.

What would partitions and file systems have to do with hardware response times?

paul1149 said:

What would partitions and file systems have to do with hardware response times?

Possible wrong partitioning with extra sector/cylinder translation.
Also read http://disablehddapm.blogspot.nl/

I've been through dozens of these drives and never had one with access times of 26ms.

I've got the drive tethered to my desktop and after backing up with play with the mbr and partitions.

I also had turned off APM via HDDScan and it did nothing. I'm also not sure whether HDDScan's control of that setting is permanent or not.

Ok, I deleted all partitions and created a new NTFS partition. Then I ran the test again, with no change. The Before pic is first. This is over a USB 3.0 connection, which I think doesn't restrict anything. IAC, I've seen access times of 10ms less over the same connection on other drives.

This drive's average access times approach that of what they call full stroke reads - the worst case scenario, when the target is on the other end of the drive. Maybe the arm of the drive is experiencing friction or other problems. Another interesting thing is how similar those two profiles are.