I have a laptop with an Intel dual core T2600 processor, which I
installed XUbuntu (Dapper) on some time ago. /proc/cpuinfo shows just
one processor, so I tried implementing the SMP kernel by running:

sudo apt-get install linux-686-smp

then rebooting. /proc/cpuinfo still shows just one processor. I even ran
'sudo apt-get update' then the above command, but no-go.

I do have an ATI Radeon X1600 video card with the fglrx driver, which I
had to do a manual install of sometime back. Not sure if that makes a
difference.

Thanks!

--john