CPUTYPE in /etc/make.conf

[Conrad J. Sabatier]

Could someone please confirm for me whether or not I'm using the best
CPUTYPE for my processor?  Sorry to ask such an idiot question, but I'm
totally new to the AMD-64 platform; only had this machine for four days
now.  :-)

CPU: AMD Athlon(tm) 64 Processor 3200+ (1995.01-MHz K8-class CPU)
  Origin = "AuthenticAMD"  Id = 0xf4a  Stepping = 10
 
Features=0x78bfbff<FPU,VME,DE,PSE,TSC,MSR,PAE,MCE,CX8,APIC,SEP,MTRR,PGE,
MCA,CMOV,PAT,PSE36,CLFLUSH,MMX,FXSR,SSE,SSE2>
  AMD Features=0xe0500800<SYSCALL,NX,MMX+,LM,3DNow+,3DNow>

Is athlon-xp the correct choice for this particular model?

Also, am I just imagining things, or is the CPUTYPE?= setting not being
honored/used by make in the amd64 environment?  The first few ports I
tried building, I didn't see any -march= flag being used.

I'm currently forcing the -march, using the following in /etc/make.conf:

CPUTYPE?=athlon-xp
CFLAGS= -O2 -pipe -march=athlon-xp -m3dnow -mmmx -msse -msse2 -m64

Is there any danger in using all of these options?  What about for
kernel builds?

Thanks!

-- 
Conrad J. Sabatier <conrads at cox.net> -- "In Unix veritas"