(1) For a starter SRT speeds up HDD from 1.5 to a max of 4x. It is limited by the "artificial" intelagence of the algorthium that controls the cache. It what is requested is not in the cache then performance is @ the speed of the HDD.
(2) Wei is a rather poor Benchmark.
... (A) It generally is only usefull to identify a problem. For example say you have a SSD boot drive and most generally are hitting say 7.8 for the specific one and you are only getting say 6.2 - You know you have a problem such as an incorrect controller ie pcide and it should be msachi or iaSTor.
.... (B) It has a deviding point 5.9 an less for HDDs to get into the 6's you need a Boot SSD. It is kind of like the way they measure earthquakes. An earthquake rated 8 is 10X larger than one rated a 7. Most of the current Gen 2 and Gen 3 SSDs are from 20 -> 40 Times faster than a HDD. A change of 2x is not a big enough change to warrent moving past the 5.9
.... (C) Even using other Disk benchmark programs, the performance is probably going to be (1) equal to the performance of the HDD as a stand alone drive or (2) inflated if it is based on the speed of the SSD.
If it feels fast, that is what counts.
You did not indicate which SSD you are using. The Intel 311 is a special SSD that uses SLC memory. If you are using one of the MLC 60 gig SSDs you would be better off using it as a OS +program Disk vs using it as a SRT disk.