This drive has some serious issues this was my post in Intel Support Community:
Last Thursday I received my brand new Dell Precision M6600. Before I started to use the system I upgraded the hard drive to an Intel 520 Series..
After dropping in the SSD, I was ready to install Windows 7 Pro. I first went into the BIOS and left the setting on RAID. After reading tons of forums, this seemed like the right way on installing the hard drive. Once complete I installed all the necessary drivers (which is a story in its self!). After, I went on the Intel website and ran the driver utility make sure everything is up-to-date. I also installed the SSD toolbox to optimize the drive.
After dealing with the BIOS not always detecting the SSD and the occasional OS freeze, I made my way into the Intel control panel. I noticed the hard drive was only running at 3GB/s, I thought that was kind of odd since the computer is capable of running 6GB/s. I decided to change the BIOS to AHCI and reinstall 7..
Once complete, I still had to deal with the BIOS not detecting the SSD and 7 freezing up, every so often. Anywho, once I re-installed all drivers and utilities. I now see the hard drive running at 6GB/s. I was a happy camper until I started to use the computer. I noticed it freezed up the more I use it.
Intel (typing this while simultaneously shaking my pointer finger) you have a serious issue with your SSD. You need to post a firmware update. Not only to fix the issue with 7 but, also for folks who have M6600 and other affected laptop/desktops; who decide to buy your SSD.