When moving a single large file, in this case a 6GB ISO, the Velociraptor 1TB drives achieved 151.3MB/s when coupled with the Duo and that increased 14% to 172.3MB/s when attached via SATA. The 520 Series managed a bandwidth of 172.9MB/s when connected to SATA, while it fell 19% to 145.6MB/s when inside the Duo.
The program copy test is comprised of many small non-compressed files (6104 files totaling 2.75GB). Here the Duo coupled with the Velociraptor HDDs provided a throughput of 133.4MB/s, while moving them directly to the SATA 6Gb/s interface improved the performance by 23% to 164.6MB/s.
Our game copy evaluation uses a mixture of small and large compressed and uncompressed files. This time the Velociraptor drives were 10% faster when using SATA 6Gb/s versus Thunderbolt. The 520 Series drive on the other hand was 39% faster when connected to the motherboard's SATA 6Gb/s port.