I'm having a problem with installation of a 9500 GT in a 730i board.
eVGA 730i with Onboard 9300 GPU; Intel Q9550 Core2Quad; 8 GB G-Skill DDR2; WinXP-64; 650w PSU. 9500 GT 1GB Video Card will not operate.
Have set BIOS to:
Initial Display: [PCIEx]
Onboard GPU: [Enable If No Ext GPU]
PCI Ex Maximum Payload Size: 
Checked PSU 12v status: [12.23v]
Prior to physical installation of card:
Deleted all video drivers, Ran Guru3D DriverSweeper, Installed eVGA driver [196.21_desktop_winxp_64bit_english_whql]
Dual monitor system: monitor 1 initializes, loads GPU script; freezes, loses video signal and then recycles through same sequence until physical shutdown. Monitor 2 does not detect any signal throughout sequence. Onboard GPU functions properly; both monitors operate on either onboard output.
Card functions properly in other machine. (Intel DP35DP)
No BIOS option to disable the onboard GPU is available; It is either [Always ON] or [Enable if no EXT GPU]. When the 9500 is in the PCIEx slot, the onboard GPU apparently disables; I connected the monitor to the onboard without removing the 9500 and there is no video signal.
I assume you selected the second option in the bios. I think that should disable the integrated graphics when you install the 9500GT. I have upgraded several graphics cards without problems, but never started with integrated and had to disable it. I think you may also need to go into device manager and disable the integrated graphics from there.
Check all your cables and connections and make sure the graphics card is properly seated in the slot.
You could try this sequence: uninstall all drivers, turn off the computer, put the card in and power up. Hopefully the computer will see that you have new hardware. You may get a very low resolution desktop until you install the drivers.
Now install the latest drivers and reboot when the comp tells you to.
Another thought, maybe you should use only one monitor at first and see if the card works that way. If it does, the set up the second monitor. I believe you have to configure the second monitor in the nVidia software.
It appears to be a board error in the PCIEx slot. I'm going through the RMA procedures now to replace the board. Went through several steps, including a drive scrub and reinstall of the operating system trying to run ths down; live & learn!