Disk-to-disk transfer rates - SATA to/from USB 3.0 is 3-5x faster than SATA to/from SATA

smyles_eh

Distinguished
Aug 25, 2011
3
0
18,510
Asus MA88T/M-USB3 Motherboard
AMD Phenom II 6-core 1090T 3.2GHz
16GB DDR-1600 (4x4)
Onboard 6-channel SATA II
WD, Hitachi and Seagate drives
Mediasonic USB 3.0 External
Seagate USB 3.0 External
Windows 7 Ultimate 64-bit

Test results:

WD 3TB (new) to WD 3TB (new)
SATA II to SATA II (onboard)
Video files (100MB - 4GB)
20-28MB/sec

WD 4TB (new) to WD 4TB (new)
SATA II to SATA II (onboard)
JPEG and CR2 (1MB - 60MB)
20-28MB/sec

WD 1.5TB (2yr old) to Hitachi 2TB (3yrs)
SATA II (onboard) to USB 3.0 Ext (Mediasonic)
Movies and TV (250MB - 4GB)
95-125MB/sec

Seagate 1TB (4yrs) to WD 1.5TB (2yrs)
USB 3.0 Ext (Seagate) to SATA II (onboard)
Movies and TV (250MB - 4GB)
85-110MB/sec

All tests done using Fastcopy 2.08, adjusting buffer size between 32MB and 1024MB to find optimum (128MB for small files, 512MB for large files)

Any idea what gives?
 

smyles_eh

Distinguished
Aug 25, 2011
3
0
18,510


I bought four brand new drives (2 x 3TB and 2 x 4TB Seagate, not WD (oops)). I installed one of each in my PC, copied files from smaller drives (5DMkII MOV Video files to the 3TB and JPEG/CR2 to the 4TB), then started to make duplicates on the other two corresponding new drives. Also reformatted 1.5 and 2TB drives, then started copying TV and movies (250MB - 4GB) to them, as well as making backups. I've tried most of the possible combinations, and each one seems to show copying onboard SATA to/from USB 3.0 is much faster than from SATA to SATA.