Quote Originally Posted by menlatin
Not during removal. I tested it right after that on the 2nd ds3. Both cores 3.52ghz @ 1.45v and 65c load.
Perhaps the fact the heatsink has been been reapplied a number of times could've caused damage to the core even if it isn't visible as a crack?

I hate to be the bearer of bad news but there's no reason that Windows XP wouldn't detect both cores on install unless there was something physically wrong, especially as you've tested it on 3 boards.