I'm using a Dell D830 laptop, and over the last few weeks it's been developing a very irritating screen flicker problem that leads to the system slowing down almost to the point of unusability.
At seemingly random times (no commonality between how long the system has been running, what I was doing, what applications were open, etc.) my screen (I use two external LCD's with the laptop closed in a dock) flickers for a moment, then the system becomes incredibly slow. The screen redraws painfully slowly--almost like what you might expect to see with generic graphics drivers installed--and the entire system is maddeningly unresponsive. The only thing that seems to be able to correct the issue is a restart.
I've checked the event logs and nothing out of the ordinary is there, and definitely nothing that's common to all of the events.
I'm running XP Pro SP2.