Thanks for all the info. I guess my laptop won't get it done if I can't write a AD2 drum track.

I've been running SPlat and AD2 on a Q9300 w/ 8GB RAM, so I'd imagine an i3 should be just fine.  
 
What type of audio interface are you using, which driver mode, and what's your latency set to?
 
Also, you want to check out "dsp latency checker" - it's possible something is driving down low latency performance at a system level (wireless, NIC, etc)