eSATA Express54 Card Speed Report from External HDD
Posted: Wed Feb 04, 2009 8:08 pm
I recently tried an eSATA dual port Express54 wide card in my T61 connected to an external 3.5" 7200 RPM SATA-3.0 Gbps capable HDD in an enclosure that offers both eSATA and USB 2.0 ports.
I benchmarked the sustained transfer speeds to/from the external HDD (to my T61 internal Seagate 160GB 7200 RPM 7200.2 SATA HDD which is jumpered to limit it to SATA 1.5 mode). I tried it with the 3.5" external HDD's SATA mode jumper set both ways (1.5 and 3.0) via the eSATA port and found little or no difference in speeds ..... about 60 MB/sec sustained transfer rates in each direction which is more than double the 25 MB/sec rates using the USB connector found on the same external HDD enclosure. So far so good
Now I understand that T61/p motherboard SATA controllers for the main internal HDD are limited to only 1.5 Gbps for various reasons, although they are backwards compatible with SATA 3.0 Gbps HDDs if the HDD jumpers are set to limit speeds to 1.5 Gbps (like my factory installed Seagate 160GB 7200.2 unit that had it's jumper set to limit speed to 1.5 Gbps from the Lenovo factory). But that issue aside, my question is what about my eSATA Express card that is 3.0 Gbps capable and the external 3.0 Gbps HDD? If the internal T61/p SATA HDD controller was theoretically capable of true 3.0 Gbps performance (which it is not because of the reasons discussed above), would the Express slot really be capable of handling true 3.0 Gbps devices? Are Express slots really that fast?
Granted that the real world transfer speeds of 7200 RPM HDDs is well below even the the SATA 1.5 Gbps thresholds and that SATA 1.5 vs 3.0 really makes no difference, I'm still curious because I believe that true SATA 3.0 allows for auto-enabling of NCQ on the newer SATA 3.0 capable HDDs which can enhance overall performance depending on the types of files being transferred or being read.
Thanks.
I benchmarked the sustained transfer speeds to/from the external HDD (to my T61 internal Seagate 160GB 7200 RPM 7200.2 SATA HDD which is jumpered to limit it to SATA 1.5 mode). I tried it with the 3.5" external HDD's SATA mode jumper set both ways (1.5 and 3.0) via the eSATA port and found little or no difference in speeds ..... about 60 MB/sec sustained transfer rates in each direction which is more than double the 25 MB/sec rates using the USB connector found on the same external HDD enclosure. So far so good
Now I understand that T61/p motherboard SATA controllers for the main internal HDD are limited to only 1.5 Gbps for various reasons, although they are backwards compatible with SATA 3.0 Gbps HDDs if the HDD jumpers are set to limit speeds to 1.5 Gbps (like my factory installed Seagate 160GB 7200.2 unit that had it's jumper set to limit speed to 1.5 Gbps from the Lenovo factory). But that issue aside, my question is what about my eSATA Express card that is 3.0 Gbps capable and the external 3.0 Gbps HDD? If the internal T61/p SATA HDD controller was theoretically capable of true 3.0 Gbps performance (which it is not because of the reasons discussed above), would the Express slot really be capable of handling true 3.0 Gbps devices? Are Express slots really that fast?
Granted that the real world transfer speeds of 7200 RPM HDDs is well below even the the SATA 1.5 Gbps thresholds and that SATA 1.5 vs 3.0 really makes no difference, I'm still curious because I believe that true SATA 3.0 allows for auto-enabling of NCQ on the newer SATA 3.0 capable HDDs which can enhance overall performance depending on the types of files being transferred or being read.
Thanks.
