Workaround: Unsupported graphics card error in Diablo III

So, you've downloaded and/or installed Diablo III. You've got your Red Bull, your comfy slippers and track pants on and you're all set for a marathon first sitting of the game ... but what's this? The night is shattered when you load up the game and get an error:

"Unsupported graphics card error"

Why?

This rather generic error signals that your video card isn't powerful enough to play Diablo III very well. It might run it, but the performance won't be great. This isn't Blizzard's fault, it's your finances - time to upgrade if you can dude. But there is hope.