graphic card is not required to render in Visualize - you can render with CPU only (if I'm not wrong). but if you're thinking of buying card then the only approved cards are Quadros.
These are the minimum and recommended hardware requirements for Visualize. They are on the first page of the Release Notes, which can be found by navigating in Visualize to Help > Show Release Notes.
• Windows®7 or newer (64-bit)
• Dual core CPU; Quad core recommended
• 8GB RAM; 16GB recommended
• 2GB free disk space; 5GB recommended
• 2GB or more GPU RAM; 4GB recommended
• NVIDIA®graphics card: NVIDIA Quadro®/NVIDIA GeForce®/Tesla with at least NVIDIA Fermi chip; Dual-GPU setup with at least NVIDIA Kepler™ cards recommended
• NVIDIA driver version 354.56
• HDR Light Studio connection: HDR Light Studio v5.3 or newer
Is this a laptop?
If so, the GPU in most laptops is not upgrade able unfortunately. I believe BOXX has a CPU expansion box which plugs into your laptop for a boost and may also be releasing a plug and play GPU version of the same concept. (Get info about renderPRO the portable render farm from BOXX)
If it's a desktop, then an upgrade to something that will make a dramatic difference to performance is easy following the advice given in this thread.