13.04 locks up randomly and becomes unresponsive
Ok, I recently "upgraded" to 13.04. The problem I have now is that the machine I have will randomly lock up and become unresponsive (not even the keyboard responds). Sometimes I have to re-boot a few times to "fix" it. I'm concerned that it's affecting my hard drive, or at the very minimum something is broken in the kernel. This same thing happened with 12.10, but I thought upgrading might fix it. This happens sometimes when I'm using FireFox, sometimes when I'm just trying to open FireFox, and other times just during general usage.
I'm still fairly new to Linux, so I don't know completely how to troubleshoot this. I'm with the whole thing.
But here's an example: I click on the icon for the dash (I think that's what it's called) and it seems like it struggles to pull that up. I did it earlier and the entire machine locked up on me, and the screen essentially turned from my standard desktop to having diagonal lines on it. Nothing worked except a soft reboot.
My machine specs are: AMD 1.8 GHz processor, 2 GB RAM, 500GB HDD. It's a custom build, and I took the video and network cards out of an older machine.
Any type of advice anyone could give would be greatly, greatly appreciated.
I did do a search, and upon a cursory search, didn't find anything related to this and 13.04.
So if there's a command or something I can do to fix this, that would be stellar.