|I presume m/b = motherboard? I don't know what a "m/b display screen" is unless the monitor is connected to the onboard graphics port?|
"i remove all hardware and fit change cmos but facing same problem"
Please explain more clearly & in more detail. Post the make/model number of your motherboard, the make/model of your processor, the type/speed & amount of RAM, etc. Is this a new build or a system that had been working? If it's a new build, did you bench-test the hardware before installing it in the case?
See the following: http://www.techsupportforum.com/190...