..disable in the Device Manager..Although some cards will auto-disable the onboard device, they don't always do that..After installing the new card and restarting the computer, check the Device Manager/Display Adapters listing for both video devices..You can disable the onboard video from there.
On a few occasions, when the onboard video was not automatically disabled, a black screen would appear at startup. I needed to restart into Safe Mode which gave basic video driver support, then access the Device Manager/Display Adapters settings, RIGHT click on the integrated device listing, choose "Disable"..After making sure the new video device was correctly "enabled" by looking at that device's properties, I could then restart into Normal Windows.
Hope this helps.
Grif
I just bought a Sony Vaio RB50, 3.2 gig hyperthreading processor with an intel motherboard. It has an empty pci-express slot x16 for video upgrade but when I looked in the BIOS you cannot disable the onboard graphics. I called Sony and well their tech support is in my opinion substandard, the same day I was told I had 2 RAM slots and well there are 4. I opened it up and looked. I was told when you install your new video card it will auto recognise it and disable the onboard. Has anyone ever had a system do this? I always had to uninstall software for previous video card, then install new card, boot to BIOS disable old video, and then load new software and drivers. I would appreciate any input or experience with this system. TIA

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