Wierd Display Problem

While working on my system just this weird display(Image Below) and my pc just got hanged as nothing on my keyboard like capslock and num lock is working and also this kind weird display occurred for the first time. After which when i restarted my pc i didn't get any display. So to cure this i remove all the connection and remove graphics card and bios battery and then put it back after which my system is back to Normal so, i wan't know what would be the problem for this kind of weird display to appear.

Also some time when start my pc, there is no display and when it keeps on restarting so again i have to disperse my pc components and re-assemble them and after that it works fine. Can any one tell what could be the problem

My PC Confihuration:
CPU -Core 2 quad 2.66 GHz
MotherBoard -Gigabyte GA-G41-ES2L
RAM - 2X2GB 800 MHz
Garaphics Card - XFX ATI Radeon HD 5770
Power Supply - Cooler Master 600w
HDD - 160 GB + 500 GB + 1TB