Server Issues: Big Forum? Bad HD? Something else?

As some of you might know, I'm a relatively small web host that runs personal and small business sites for clients. Recently, my server's been going down with increasing frequency. Being someone used to having a month or so of uptime between scheduled outages for maintenance done at my and my clients' convenience, having my server unexpectedly go down twice a week is a royal pain.

One of my clients is having me host a forum. They've currently got 180 users, of whom no more than 10-14 will be on at peak times, and the forum's accrued around 12500 posts over the past eighteen months. The forum's running PHPBB on a MySQL database.

My server is a P4 3.0 GHz with Hyperthreading, 1 GB of RAM, and has two SATA hard drives. It was installed about six months ago, and is running on CentOS with CPanel/WHM.

When I run:
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I often see a lot of CPU time devoted to iowait.

Can anyone tell me if a normal, healthy, P4 with hyperthreading, 1 GB RAM, and a SATA hard drive ought to be able to handle the load from the forum I'm hosting?

 

 

 

 

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