Thanks Emo for responding

Well, my computer is a DELL dimension 3000 with P4 3.0 HT CPU, 512 RAM, 160 Hard drive, Video card is Geforce 5200 with 128 RAM. Well, following your suggestion, I rebooted my system and reopened Maya 6 without other program running save anti-virus and firewall, but it still like that Further more, I don't think that's a memory issue, as I have a system resource management tool, and you can see in the 2nd picture at botton-right corner, next to the clock, there is a small black box with number 114, which is how many RAM left. So...

I tried to apply a previous work as the default scene using the New Scene option box, but when starting a new scene, the screen still look like that :angry: While I can open that scene without problem. All grid are there when switching to four views. Weird hum?