Dell Dimension 2400 PC Desktop "computer screen fades dark" Questions

...computer and get into the BIOS. check if the line is there also. then plug in an external monitor into the VA connector of the system and check if the line appears there also. If in both the cases, ...

...computer.The problem I'm having is,the color constantly fades in and out,quite a bit.I still get color,but when it fades out,it's not "true" color.The reds looks pink,the blues look ...

screen just goes blank (not completely dark just blank. Nothing else appears although I can tell the computer is still on. try starting in safe mode. when you power on the PC, start tapping the F8 key