Sepherosa Ziehau has added updated the ‘ecc’ device, for Intel E3-1200 series systems. What’s it do? It will report on memory errors, and potentially fix them.
You should have ECC memory in your server already. If not, you oughta.
Update: as Sascha Wildner pointed out, ecc(4) already existed, but didn’t support Intel controllers. Also, the Xeon X3400 series is supported now too.
We already had ecc(4) before sephe’s work. What he did was to add support for Intel memory controllers and change the way it attaches.