GPGPU Question (4x Titan X)

[Thatguy]

 

Is this normal? Why are the memory read speeds so low on gpu 2? GPU 3 & 4 produce the same memory read speeds as gpu 2. Thanks.

[Fiery]

For video cards memory read and memory write speed reflect the performance the GPU can transfer data from/to the host (CPU) through the PCI Express link. In your situation GPU2 seems to be using half the PCI Express bandwidth. It is usually due to it having only x8 link, while your primary GPU should have the full x16 link.