dmesg lists cpu info. On FreeBSD, "sysctl -a" does also.

rocky# dmesg | head
Copyright (c) 1992-2008 The FreeBSD Project.
Copyright (c) 1979, 1980, 1983, 1986, 1988, 1989, 1991, 1992, 1993, 1994
        The Regents of the University of California. All rights reserved.
FreeBSD is a registered trademark of The FreeBSD Foundation.
FreeBSD 7.0-RELEASE-p6 #1: Tue Dec  2 09:02:01 EST 2008
    root@localhost:/usr/obj/usr/src/sys/ROCKY
Timecounter "i8254" frequency 1193182 Hz quality 0
CPU: AMD Athlon(tm) 64 X2 Dual Core Processor 5200+ (2605.45-MHz 686-class CPU)
  Origin = "AuthenticAMD"  Id = 0x40f32  Stepping = 2
  Features=0x178bfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,MCA,CMOV,PAT,PSE36,CLFLUSH,MMX,FXSR,SSE,SSE2,HTT>