simple make.conf question

I feel like a tard having to ask this but i'm fairly new to freebsd...


I'm running Freebsd5.2.1 stable and I am still familarizing myself with all it's working components etc. I'm slighty confused with /etc/make.conf. Mine reads as follows :

-- use.perl generated deltas -- #
# Created: Thu Nov 11 21:31:23 2004
# Setting to use base perl from ports:
PERL_VER=5.6.1
PERL_VERSION=5.6.1
PERL_ARCH=mach
NOPERL=yo
NO_PERL=yo
NO_PERL_WRAPPER=yo


Which i guess is what freebsd created for me when i installed it . With 5.2.1 i compiled my own kernel disabling smp and some other non major things. My question is that I want to basically add a CPUTYPE=athlon-xp and of course CFLAGS. Everything I've read up on about make.conf just involves people upgrading thier bsd versions. So is there a way just to basically upgrade the make.conf without the version upgrade?

ok. i've done enough reading to figure this out on my own....

I'm just curious now to know what optimizations i should use.

I only have about 512mb of ram and a amd 2600 Throughbred
Thnx

I seem to be ahead of myself... I went ahead made my changes to make.conf


CPUTYPE=athlon-xp
CFLAGS= -O -pipe

USA_RESIDENT=yes

SUP=/usr/local/bin/cvsup
SUP_UPDATE=yes
PORTSSUPFILE=/root/ports-supfile
SUPFLAGS= -g -L 2


# -- use.perl generated deltas -- #
# Created: Thu Nov 11 21:31:23 2004
# Setting to use base perl from ports:
PERL_VER=5.6.1
PERL_VERSION=5.6.1
PERL_ARCH=mach
NOPERL=yo
NO_PERL=yo
NO_PERL_WRAPPER=yo
WITH_LAME=yes


recompiled my kernel and everything looks ok... Really didnt do a mergemaster because i figured it wasnt needed.

If anyone see's anything that i could add to this to make my box more efficient i would appreciate the advice.. Sorry for creating a thread then just figuring out the answer myself..