Optiplex 990 (E-2011) and Intel HD Graphics

Hello,

I am running an Optiplex 990 (from early 2011) with a Q67 motherboard and the Radeon 6350.  I'm currently running two displays on the graphics card using a DVI splitter, and my screens are fine.  However, I am also trying to get a third display working using the onboard DisplayPort input and my computer isn't even detecting the display.

All three monitors are P2210s, and I have already enabled Multi-Display Graphics in the System BIOS.  I then tried downloading and installing the Intel HD Graphics driver from Dell's support page for my model, but the install failed.  The installation log is attached as a text file.

If someone could assist me with figuring out what the issue is and how to fix it, preferably without having to install another GPU (I won't be able to put in a procurement for a new GPU for a good while), I would be very grateful.

Per Laborem ad Astra,

JbstormburstADV