|Thanks for the reply.|
Motherboard's integrated graphics (onboard video) is not working. Monitor light blink.
And I have added external card AGP.
And power supply is capable of handling the load of a discrete card.
It doesn't require aux power connection from the power supply.
After cleaning the RAM it shown the POST screen one time but after that monitor just display the HIS logo as described above.
With the above test I thought it is ram issue. So I have taken working RAM but same result.