Look under linux image, and/or image headers.....you'll need both. I just built a new tower not to long ago and it runs an AMD Phenom II 3.2 Ghz Core 2 Duo and I have opened up 2 extra cores of which LMDE sees all of them (4 cores) and it runs great. Anyway, go into Synaptic, go to the section on the left, scroll down to "kernel and modules", then in the search window @ the top, type; linux image and it will give you all listings and just look for the one wyroak mentioned....specifically you're looking for linux-image-686-pae.....hope this is helpful.....cheers.
Dell Latitude D820/2.33Ghz Core2Duo Intel/4GB Crucial/320GB Samsung HDD/nVidia NVS 120 256MB
Win7 Bus 32 bit/LMDE-Sid-MATE 32/64 Tracking Sid