Gravoth if you have an integrated GPU there has to be either an HMDI, VGA or DVI output on the mobo. Plug your screen into that.
If your GPU is overclocked, disable the overclock. To be sure, uninstall any GPU overclocking software you might have and disable the associated services in msconfig. Artifacts are often caused by bad VRAM OCs (although they don't usually look like what you describe).
By the way I used to have artifacts with a perfectly fine GPU. They simply disappeared after carefully wiping the driver and re-installing. It might even be your motherboard or your PSU not providing enough power. That said, boot artifacts are usually synonymous with something being bricked.