3DMark PCI Express Test

3DMark has a new feature test available, it specifically tests PCI Express performance.  We wanted to run this test just to see how the video cards compare.  We are running every video card on a Ryzen 7 2700X CPU with the X470 chipset, this means the maximum PCI Express supported is PCIe 3.0 x16.  That theoretically has a maximum potential of 15GB/sec, but with overhead and latency should be around 13GB/sec.  We thought it’d be interesting to run the test anyway and see what happens.  Of course, it will be interesting to compare this performance with PCI 4.0 when we test that in the future. Note, in the graph below all video cards are compared by price, from the most expensive at the top to the least expensive at the bottom.

AMD Radeon RX 5700 XT and RX 5700 PCI-E 3.0 Performance

From this graph you can actually see something interesting.  The AMD Radeon RX 5700 XT and RX 5700 actually provide slightly faster PCIe 3.0 performance over the NVIDIA video cards.  They come in at 13.8GB/sec of bandwidth, while all the NVIDIA video cards are at 13.08GB/sec.  It’s a small difference, but very consistent in our testing.  It could point to overhead and latency being a bit better with the 5700 series, just speculation.  It will be interesting to compare to PCI Express 4.0 in the future.