bedazzled, have you tried the CPU in your MSI motherboard, which board is it?
I could probally help you get the 2500K CPU to 4.8GHz if it still works and 4.6GHz on Auto Volts using power saving features if it's a similar motherboard to mine.
Tried it in the MSI board with some spare sticks of RAM and it won't post not even a beep. Probably can't rma it as I got it from another e-tailer and their website states everything must be returned in it's original packaging, it was a retail cpu and I don't have the intel box anymore.