Help 500 internal server errors

[moonmoth]

Hi Guys,
The last few months I've been getting 500 internal server errors. The log files show the exact same problem repeated through the day, every day.
: [Wed Jun 11 04:59:19 2008] [error] [client 72.44.51.168] FastCGI: comm with (dynamic) server "/var/www/fcgi/php-cgi" aborted: (first read) idle timeout (30 sec)
[Wed Jun 11 04:59:19 2008] [error] [client 72.44.51.168] FastCGI: incomplete headers (0 bytes) received from server "/var/www/fcgi/php-cgi"
[Wed Jun 11 05:00:38 2008] [error] [client 72.44.51.168] FastCGI: comm with (dynamic) server "/var/www/fcgi/php-cgi" aborted: (first read) idle timeout (30 sec)

I have two databases on the same host and both go down at the same time. The hosts seem to keep scratching their heads and thus far the problem remains.
I know naff all about the server end of things so I'm as much use as a chocolate tea pot.
The errors began on 3.6 and continued when I upgraded to 3.7. What I don't get though is the other database hangs and throws the same 500 error at the same time; like I said, techie I'm not but when the same thing happens, same time on a completely different db I tend to suspect server error rather than anything I've done........ but will crimson nicely if proven wrong.
Any suggestions? Pretty, pretty please..........