2.6.27-3rt kernel only sees half of dual core processor

[ekafton]

Just updated to 8.10rc. The new kernel only sees and uses one side of Intel dual core processor. Cannot use the new kernel this way because it is extremely slow. Have had to drop back to kernel 2.6.24-19rt to use laptop. Does anyone have any ideas on how to get the 2.6.27-3rt kernel to use the whole processor?