AFTER START THE PC JUST AFTER FEW SECOND DISPLAY FREEZ AND SOME LINES APPEAR ON SCREEN THEN BSOD HAPPENS CAN I INSTALL DRIVER BEFORE INSTALLING THE G.CARD COZ WHEN I GO FOR INSTALLATION OF CARD DRIVERS IT SAYS THERE IS NO NVIDEA PRODUCT FOUND IN UR PC .,
To my knowledge, it is generally tough to install graphics card drivers without the graphics card installed. Many times the installer needs to detect the graphics card.
Is this your motherboard (I ask because you did not include the B3 part)?
If so, then it should be able to use that graphics cards (I assume you meant an XFX 9500GT, not SFX).
You did not answer all my questions? Do you see the POST messages? Can you get into the BIOS? Can you get into Safe Mode?
It is still not clear if your computer is freezing before Windows even starts or if it is freezing only after Windows starts. If it is happening before Windows actually starts (i.e. you are not even getting POST or able to get into the BIOS, then it could be a hardware problem with either the graphics card or the mobo. If it is happened after Windows starts, then there is likely something Windows does not like about the card (such as maybe a graphics driver for another card already install, which is why trying Safe Mode is suggested).
Did you have a different graphics card installed on this computer? If so, did you remove the drivers for the previous graphics card?