There are many people running Ivy builds with the chipset intel 4000 graphics. There are also many commercial machines that have been sold for PT with this setup. There have been ZERO problems with this setup from my build. Not even a hiccup. The chipset graphics are perfect for PT's and the USB 3 is great. I have been using onboard unapproved FW chipset also.
Many things that you read here just make no sense
and Ivy is one of them.
Save some loot and get a nice water cooler and an IVY setup. Runs almost silent. You can O/C your brains out... if that is your bag! No need for a graphics card.