Wayne Sheffield offers advice on TCP Chimney Offloading:
With all of these changes to the OS, which setting should we use for SQL Server? In general, for all of these operating systems, I recommend that TCP Chimney Offload be disabled – because you can see odd connectivity problems in any other state. Notice in the above quote that Microsoft says that this feature is best used for applications with long-lived connections that transfer large amounts of data – hopefully your OLTP database is performing lots of short-lived connections and they are not transferring large amounts of data (if they are, I can help you with that!).
Definitely worth a read.