I have an iMac 21.5" Late 2009 model in which I have replaced the optical drive with a SATA sled and an OCZ Agility 3 120GB SSD. I have partitioned that 120GB into 60GB for OS X Lion 10.7.4 and the other 60GB for Bootcamp Windows 7 Ultimate. On a whim I decided to benchmark the SSD drive using Drive Genius. I was surprised at how low the numbers were so I opened, "About this Mac" and navigated to the SATA information. On both the internal hard drive WD Green 1TB and the SSD the negotiated link speed is only 1.5Gbps (SATA 1). I checked my other Macs that I have with SSD drives (MacPro1,1 with Intel 320 120GB, MBP13 with Patriot Inferno 60GB, and Macbook Aluminum 13" with OCZ Vertex Plus 60GB) and all of those report negotiated link speeds of 3Gbps (SATA 2) as they should. I have tried SMC reset and PRAM reset to no avail. One important thing to note... I originally had this SSD in my iMac 2008 24" and moved it over to this 2009 21.5" so the original Lion install was on a different model of iMac. So I am wondering if it is possible that this is some sort of driver issue or is it a hardware issue? I could take the step of doing a fresh Lion installation on this iMac (I have a time machine so getting back to where I started is easy). This would maybe answer the question of whether it is just a driver issue. But before I do that I was wondering if it is even possible that this is the issue. It sounds more like a hardware issue to me since negotiated link speed should be something that the SATA controller and SSD/Disk sort out by themselves. I thought maybe it was the SATA Sled but it seems to me that is just passing the signal through with no interface chip. Plus that would not explain why the WD 1TB drive is only negotiating SATA 1 speeds. I have the same model in my MacPro and it has no issue with SATA 2. Also, if I boot into Windows I know I am in IDE mode and not AHCI but the benchmarks also suggest that I am only at SATA 1 speeds. If I go into device manager I don't seem to be able to find information concerning whether it is SATA 1 or 2. Any thoughts?