System hangs after X hours

[Steve Loftis]

I recently installed FreeBSD 5.1 and I am completely impressed with it. 
I really enjoy just how it works so well.

My only real problem is this... after my system staying on for a while, 
it just simply quits responding. The screen goes black, the input 
devices such as mouse and keyboard don't help bring it back either. I 
have to press the reset button. Once it goes to the bootloader, the 
keyboard still doesn't work.

So i unplug the keyboard and mouse, and plug it back in while the system 
is off (these are PS/2 peripherals, btw). After I do that, it works just 
fine, but that is until it decides to quit responsing, oncemore.

Any insight into this? I have modified my kernel, but only to add sound 
support. Help would be greatly appreciated.

--Steve-0