Monitor is going to sleep mode

Hi,
My CPU is getting powered on but signal from cpu isn't going.I tried with following steps;
1.Removed RAM and CMOS battery.Cleaned properly and reinserted.
2.Checked VGA Cable.No problem found with cable.
3.I have checked the monitor by connecting it to other cpu .Its working fine.
4.Replaced CMOS battery with new one.
Still have problem...Kindly assist me as soon as possible...Thanks in advance.......