Heat, Vcore, Etc. will be about the same, but will depend to some extent on the individual chip itself.
The Barton will actually be easier to cool however, because its die has a slightly larger surface area, so a greater area is in contact with the heatsink.
and AMD_MAN is of course right - the Barton will outperform a tbred at the same clock speed/FSB.
BTW - you'll probably be able to get a slightly higher OC out of the barton anyway.
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$hit Happens. I just wish it would happen to someone else for a change.