BSOD on Windows SBS 2011, randomly occuring

Hi guys, hope you can help. I have a Dell PowerEdge T320 running Windows SBS 2011 (much the same as 7) and it randomly gives a blue screen of death. I couldn't get the SF Diagnostic Tool working, as it came up something about the .NET framework, but I did get the minidump file if this is of any use to you guys. This has happened around 3-4 times, but today I was just browsing the internet...