So, you think that method would work, the other person had to leave the IGP plugged in to a 2nd monitor to get it to work? If so then I wouldn't need the additional GPU, just follow those steps (that's actually my thread you linked, in it I quoted the original poster who used that method.) Further reading last night seems some manufacturers support legacy & UEFI, and others don't; could that be part of it?
Here's the info I've collected regarding this so far:
Legacy class 0 bios sytems need cards that support msdos VESA mode 103.
See if there is a PCI SERR MSG setting in bios. turn that to off.
this option is in the maintenance section.
You cannot use the onboard video AND a PCI-E video card. Once a card is in the X16 slot you MUST use that card only.
Don't know if this is useful? So you think I don't need to buy that GT710, and can just use the integrated graphics following these steps:
Step 1: Download all relevant drivers for new GPU
Step 2: Reboot into your BIOS and make sure your integrated graphics option is set to AUTO. Save and reboot
Step 3: Power everything off, unplug the power cable and hold the power button until all LED's are gone. Unplug everything and remove old GPU.
Step 4: Install new GPU, and hook up the VGA cable from your computer to your monitor.
Step 5: Using integrated graphics (If a black screen pops up saying something about graphics and rebooting, you haven't set your BIOS correctly. Repeat step 2 and come back. This can be done with the new GPU installed, so no worries) load in to your computer and it should automatically download any and all updates and drivers for the new GPU. If not, go download them.
Step 6: Once all installations are complete, reboot your system. You should now be free to use the new GPU instead of the integrated graphics. Feel free to go back in to BIOS and disable your integrated graphics option, but you shouldn't have to as long as your monitor is on the same input setting as your GPU.
(but don't disable the integrated graphics option