[CentOS] Interpretation of a hardware error

Hey, folks,

I've just started seeing
Apr 12 13:09:59 <server> kernel: [Hardware Error]:
MC4_STATUS[Over|CE|MiscV|-|AddrV|-|Poison|CECC]: 0xdd0accf2001d011b
Apr 12 13:09:59 <server> kernel: [Hardware Error]: Northbridge Error (node
1, core 1): ECC error in L3 cache tag.
Apr 12 13:09:59 <server> kernel: [Hardware Error]: cache level: L3/GEN,
tx: GEN, mem-tx: RD
Apr 12 13:09:59 <server> kernel: [Hardware Error]: Machine check events
logged

I'm guessing, unhappily, that this means the on-chip cache, not DIMM. Does
anyone here know?

       mark, who'll be the one to call it in under warranty....