mysql - Having trouble keeping a 1GB RAM Centos server running

This is my first time configuring a VPS server and I'm having a few issues. We're running Wordpress on a 1GB Centos server configured per the internet (online research). No custom queries or anything crazy but closing in on 8K posts. At arbitrary intervals, the server just goes down. From the client side, it just says "Loading..." and will spin more or less indefinitely. On the server side, the shell will lock completely. We have to do a hard reboot from the control panel and then everything is fine.

Watching "top" I see it hovering between 35 - 55% memory usage generally and occasional spikes up to around 80%. When I saw it go down, there were about 30 - 40 Apache processes showing which pushed memory over the edge. "error_log" tells me that maxclients was reached right before each reboot instance. I've tried tinkering with that but to no avail.

I think we'll probably need to bump the server up to the next RAM level but with ~120K pageviews per month, it seems like that's a bit overkill since it was running fairly well on a shared server before.

Any ideas? httpd.conf and my.cnf values to add? I'll update this with the current ones if that helps.

Thanks in advance! This has been a fun and important learning experience but, overall, quite frustrating!

Edit: quick top snapshot:

top - 15:18:15 up 2 days, 13:04,  1 user,  load average: 0.56, 0.44, 0.38
Tasks:  85 total,   2 running,  83 sleeping,   0 stopped,   0 zombie

Cpu(s):  6.7%us,  3.5%sy,  0.0%ni, 89.6%id,  0.0%wa,  0.0%hi,  0.1%si,  0.0%st
Mem:   2051088k total,   736708k used,  1314380k free,   199576k buffers
Swap:  4194300k total,        0k used,  4194300k free,   287688k cached

Answer

If your server cannot handle spinning up 30-40 httpd processes (it can't), then don't let it. I go into a lot of detail regarding LAMP configuration in my answer to this question. The examples I give are for a 512 MiB VPS, so don't just blindly copy the configuration "per the internet". :)

Short version: scale back your httpd MaxClients and ServerLimit variables to prevent 30+ httpd processes from spinning up. I'd start with something like 10 or 15 depending on the average size of your processes, and how much room you've given MySQL. Note that httpd's behavior will be to refuse requests when all client processes are busy.