MCP73VT-PM User Manual

If the video card is a PCI video card, installing it DOES NOT disable the onboard video.

If you use a PCI card that has an old video chipset that first came out before about 1999, many of those are NOT compatible with being installed on mboards that have onboard video, unless you can disable the onboard video by means of a jumper on the mboard – the video chipset cannot co-exist with the onboard video and both the onboard video and the video on the card will try to display at the same time – the video on the PCI card will be really messed up. I haven’t seen a mboard that has such a jumper you can move or remove to disable the onboard video since the earliest Pentium mboards in the early 90’s. E.g. I have an ATI Xpert 98 (Rage XL video chipset) PCI card that that applies to.

If the video card is a PCI-E X1 card, installing it in a PCI-E X1 or a PCI-E X8 or a PCI-E X16 slot MAY NOT disable the onboard video.

There’s no setting that can disable the onboard video in the bios. When the onboard video is not disabled when you install a PCI or a PCI-E X1 card, there is nothing you can do in the bios other than reduce the amount of ram installed in the mboard that is shared with it. In Windows, you can disable Windows from enabling the onboard video when there is more than one Display adapter listed in Device Manager by RIGHT clicking on the entry for the onboard video and choosing Disable (choosing Un-install won’t work – Windows will detect the onboard video again the next time you boot the computer).

The only thing setting the Primary video or Initialize video first or similar setting does is provide info that Windows needs – e.g. if you set that to PCI-E, a PCI-E card will be able to use it’s enhanced capabiliities in Windows via it’s specific drivers having been installed – if that setting is set to onboard video or PCI, and the video card is PCI-E, the specific drivers loaded for the PCI-E card WILL NOT be able to use the card’s enhanced capabilities in Windows properly – you still get video in Windows but it can’t work properly with that improper setting in the bios.

…….

If the video card is a PCI-E X16 card….

In that case……..
– the video card in the slot is damaged
or
– the PCI-E X16 slot is damaged
or
-the mboard is otherwise damaged.

ATX power supplies are always supplying power to the mboard in some places including some of the contacts in the card slots and in the ram slots, even when the computer is not running, as long as the PS is connected to the mboard, the switch on the PS is on, and the PS is receiving live AC power.

Did you remove the AC power to the PS at ALL times when you were plugging in and unplugging the card ?

Try the video card in another computer.

Try another PCI-E X 16 video card in this computer.