I also have very similar performance results on my 120G drive. My configuration is as follows:
Gigabyte H55M-USB3 main board
Windows 8.1 Pro
Intel Core i7 870 2.93GHz
AHCI is enabled.
SSD is used on 3GB/s port since my motherboard only has these available.
I would like to thank you beforehand for your time and support.
