I think the issue will be down to instruction sets, if the OS is aware of the difference at all. But my point is, if the software doesn't take advantage of parallelism, dual core is pointless. You may as well just have the fastest single core processor available, because it will be cheaper and you will not notice any difference in speed between and single and a dual core.
"B..b..but man, it'll be like having TWO processors at once!"
Well, yes it will, with one of those processors fast asleep about 95% of the time...