NVIDIA's Quadro 4000 for Mac, more affordable speed for the right application by Scott Simmons - ProVideo Coalition
Amazon.com: Epic IT Service - Quadro 4000 for Mac, for Apple mac pro, 2GB GDDR5 PCI Express Gen 2 x16, DVI-I DL, DisplayPort, CUDA and OpenCL Profesional Board (Attn: Legacy Model) : Electronics
Amazon.com: Nvidia Quadro 4000 256CORE Cuda 2GB Dual-link Dvi Dual Disp Port : Electronics