Found a strange issue after upgrading from a 2x WD 640GB Black RAID 1 to 2x WD 1TB (WDC1002FAWX-009A8) RAID 1 array.
Both drives are connected to the 3.0Gb Intel Z68 (blue) ports on my Asus P8Z68-V Pro motherboard.
When I look at 'Advanced' details in the Intel Rapid Storage utility, one drive shows SATA transfer rate of 3 Gb/s, while the second drive shows SATA transfer rate of 1.5 Gb/s. Both drives were purchased together, both Firmware 05.01D05, both manufactured the same day.
I'm running the latest P8Z68-V Pro bios and Intel RST 10.8.0.1003.
I don't recall checking this with the previous 640GB Black RAID 1 array, but I still have one of those drives in the system (now for backup purposes) and it shows 3Gb/s.
The drive showing the 1.5Gb rate is on port 4, and the drive showing the 3 GB/s rate is on port 5.
Other drives and SAT transfer rate status:
- Crucial m4-CT128M4SSD2 Port 1 6 Gb/s
- OCZ Vertex2 Port 0 3 Gb/s
- WD 640GB Black Port 3 3 Gb/s