Currently 115 users online:
top - 20:21:43 up 20:15, 1 user, load average: 0.72, 0.85, 0.99
Used mysqltunner perl script and followed instructions and deactivated plugin "postviews", and cpu load decreased. I go to activate plugin "postviews" again and will see what happens.

---------- Post added at 07:40 PM ---------- Previous post was at 06:32 PM ----------

After read here and there.... http://boomshadow.net/tech/php-handlers/

I enabled php handler FastCGI and seems that cpu load decreases a little (ram usage increase arround 60MB, affordable).

Load Averages: 0.86 0.71 0.81

After one hour:
Load Averages: 0.53 0.61 0.63

I think that now all is normal