First we have the tool 3DM2 Management Utility with this tool you can easily login to your 3ware controller and set up loads of stuff. One of those things is upgrading the firmware. If you know how to use a browser, you can do this!
The mirror is my own FTP, so no weird repackages or other crap, just the original files!
Download the new firmware LSI/3ware | Mirror
Download and install the tool. (needs Java!) LSI/3ware | Mirror
Download Driver for Windows 7/server 2008r2 x64 LSI/3ware | Mirror
Run the Tool from this short-cut.
It will open (a new tab) in your browser.
https://localhost:888/
Login with the administrator account. the standard password is 3ware
Now you hover over the tab Management and click on Maintenance
At the bottom you see a box where you can upload the firmware.
Browse and select the firmware called prom0006.img and click open. After that, click "Begin Update"
You will be prompted with a warning screen, read it and take actions if needed. The next screen showing you your current firmware and the new firmware.
Read the last row, it will tell you weather you can continue or not. (you might need to install an older firmware version first before you can upgrade to the latest version).
Unfortunately I did not make a screen-shot of this point, so please if you did send it to me so I can add it!
Upgrading takes 1 or 2 minutes and might freeze your screen. Don't start clicking everywhere, just wait.
now we repeat this step and upload the file prom0008.img
This time you will not be prompted with anything. after a minute you can reboot, use alt+3 to enter your raid-controller config and create your new raid array!
Congrats, you can now use 4Tb disks on your 6950SE!