FreeBSD 7.0 amd64 FAMP Server RAM problem

[Benjamin Adams]

Hello everyone.  I'm running a website (http://www.FreeBSD-World.com/)  When
the RAM is used up and moves to inactive the pages stop loading 100%.
Pages will stop halfway and sometimes I will get a display of what is in the
httpd.access log.

Server is running
FreeBSD 7.0
PHP 5.2.6
Apache 1.3.41
MySQL 5.0.51a

Top output:
last pid:  7607;  load averages:  0.07,  0.12,  0.06    up 0+02:59:32
17:40:27
72 processes:  1 running, 71 sleeping
CPU states:  0.0% user,  0.0% nice,  0.3% system,  0.3% interrupt, 99.4%
idle
Mem: 79M Active, 23M Inact, 221M Wired, 240K Cache, 156M Buf, 7590M Free
Swap: 4096M Total, 4096M Free


I just reboot the machine so it will be sometime before ram is full again.
Configs:
MinSpareServers 5
MaxSpareServers 10
StartServers 5
MaxClients 150
key_buffer = 16M
max_allowed_packet = 1M
table_cache = 64
sort_buffer_size = 512K
net_buffer_length = 8K
read_buffer_size = 256K
read_rnd_buffer_size = 512K
myisam_sort_buffer_size = 8M


should I change something? using the defaults.
Server has 8G RAM and Quad Core AMD

Thanks for taking the time to look!!!

Ben Adams
http://www.FreeBSD-World.com/