Instead of blue screen, I experienced freezing

I didn't experienced any blue screen of death today. However, I found that the Internet connection was not working right after I opened the lid of the x60t. I didn't pay much attention and continue typing my diary. Then I touched the WiFi setting and that was the time when the machine frozen up. There was no blue screen, but simply frozen up. In order to preserve my writing, I used my PDA to write down what I wrote on the screen, and then reboot the machine.

I think it has something to do with how VRam was being used. So I think that next time before I go to sleep, I should switch the machine into single screen display mode.

This is annoying indeed.