ProPresenter will run on most any well equipped machine that meets current operating system specifications from Apple or Microsoft. That said, many computers are designed for home and office and only ship with an Intel "integrated" GPU. While these will likely work, these integrated GPUs may not perform as well with multiple graphics outputs as a more powerful, dedicated GPU. There are two primary manufacturers of "discrete" GPUs: NVIDIA and AMD/Radeon.
As there are a wide variety of discrete GPUs, it's hard to specify what will and won't work well, but anything that supports OpenGL and OpenCL 3.2 or higher with dedicated video memory of 4GB or higher should work fine for most scenarios that have multiple outputs at 1080p60. Higher end cards with more graphics memory can support even more outputs at higher resolutions. Also, remember that all ProPresenter outputs are rendered in just one GPU, regardless of whether the output is through a Blackmagic device, an NDI feed, or a second graphics card (so don't get a second graphics card thinking it is going to boost performance… you're better off getting a single, more powerful graphics card).
Currently, we do not have any specific cards that we recommend, but with the power of ProPresenter 7, you should stay in or above the NVIDIA GTX series cards or AMD Radeon HD or RX series cards.
Some laptops include switchable graphics, with an Intel card plus a discrete GPU. When running on these machines, specify that you want to use the faster graphics processor for optimal performance.