System failure imminent?

[[TC]►Nick◄]

Hi guys,

I was playing LFS (I'd only been on around 15 minutes) when the fps dropped and the sound went funny. The actual in-game fps counter showed no deviation from the normal fps, however it was visibly lower, almost spiky, and the sound also made a "spiking" sound. I also started to lag out, however I could still drive, as the game had not locked up. Once I lagged out, however, LFS seemed to jam, and CTRL + ALT + DEL was the only way to get out the black screen, however I could not shut down LFS, so I forced my laptop to shut down.

Upon startup, this was what had happened to my background:

Spoiler (Click to View)

The photo should continue down into the taskbar, however it cuts short into grey, with a rainbow to the right of the screen. A quick restart has "solved" that symptom, but as this is the second time this has happened, I thought I should seek some advice.

I tried Googling it, but there were so many varied answers that I thought it might be better to ask directly, so no cheeky LMGTFY links please.

Any help would be appreciated, and if it's something terminal, you can expect a "Help me build a new PC" thread sooner than I planned.

Cheers,
Nick