A lot of 500 error with wordpress

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ISPCP 1.0 rc7

Operating System : Linux (32 Bit)
Server : Apache
Memory usage : 22.36 MByte
MYSQL Version : 5.0.32-Debian_7etch8-log
SQL Mode : Not set
PHP Version : 5.2.0-8+etch13
PHP Safe Mode : Off
PHP Allow URL fopen : On
PHP Memory Limit : 128M
PHP Max Upload Size : 2M
PHP Max Post Size : 8M
PHP Output Buffer Size : N/A
PHP Max Script Execute Time : 30s
PHP Exif support : Yes ( V1.4 )
PHP IPTC support : Yes
PHP XML support : Yes


And the error log:
mod_fcgid: process /var/www/virtual/argiaikastola.com/htdocs/cast/wp-admin/admin.php(18670) exit(lifetime expired), terminated by calling exit(), return code: 0



I have changed several parameters of the configuration of fcgid (to increase timeots time), and now i have no error 500... but the load of site is veeeeeeeeeeery slooooooooooow (but when loaded the navigation is very very fast for a time, then again slow), the trouble is not the server (has several websites even with wordpress (older versions) and all is ok...
I have tried wordpress 2.86, 2.90 and 2.91 (all the same trouble)
I have one site with wordpress 2.71 without trouble...