No video after attempted USB 3.0 PCIe card install on Dell Optiplex 790 MT

smileman

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Jan 25, 2012
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I have a Dell Optiplex 790 MT on Windows 8.1, which I use to run two monitors off of an older 3700 AMD Radeon 6450 HD 1GB FH DVI 1.

Today I installed an Inateck Superspeed 4 Ports PCI-E to USB 3.0 Expansion Card - Interface USB 3.0 4-Port Express Card Desktop (without attaching the SATA power) and now there is now video to either of my monitors.

Installation and troubleshooting notes:

I temporarily removed the AMD graphics card, which was powering the dual monitors, so that I could more easily install the Inatek card. I also used some compressed air to clean the interior of the PC. I was sure to push the power button on the PC after turning off the UK outlet power cutoff switch.

After putting everything in place and putting the lid back on and powering up I no longer have any video. Power seems to be fine for the Dell computer and monitors, but no BIOS screen or anything else is showing on the monitors.

Troubleshooting already attempted:

-I tried removing the Inatek

-removing and reattaching the AMD

-putting the AMD in a different PCIe slot

-removing the AMD and plugging just a single display port monitor cable into the Dell's built-in display port slot

-unplugging my DVI and Display Port monitor connections and plugging in just a VGA cable

-I tried using my Chrome remote desktop from my laptop to see if I could login to the Dell there but it says the computer has not been seen. I would have thought if the Dell is booting to the login screen I should be able to login in via remote desktop from my laptop.

Desperate for help. Thanks.
 
If your onboard video does not work, chances are that the motherboard is bad. Did you check the monitor side of the connection and maybe try a different monitor?

Try restting the BIOS by removing the CMOS battery for about 10 seconds with the system unplugged from power and try again.