For GPU mining, we highly recommend the graphics card from AMD R9 2xx / RX4xx series. And we take the 250W Radeon R9 280 VGA as the example for building the Bitcoin mining rig here. The AMD Radeon R9 280, the performance-focused graphics card is one of the ideal graphics cards from this VGA series to pair with the TB85 with 6 PCI-e slots to maximize the mining efficiency.

You can easily check the power of your graphics card and mining efficiency at