RAID Controller Recommendation needed

I need to upgrade the hard drives on my IBM System X3400 server, Type 7975.  I currently have three 160 GB SATA drives connected to the IBM ServeRAID-8k SAS controller.  When I attempted to replace them with three 2 TB SATA drives, they were not recognized by the controller.  I was told I needed to upgrade to a newer RAID card.  I called IBM for a recommendation, and they told me I should look for a PCI e or PCI x card.  There seems to be a lot of cards available in these formats at quite a broad price range.  Does anyone have a recommendation for which to choose?  I'm using this server as a file server and a SQL server.

Thanks