PCI Express Generation 3 brings no performance benefits for the HD 7970

/ 5 years ago

PCI-E Gen3 is the next big thing for motherboard marketing as the USB 3.0 advertising fad starts to fade away quite rapidly. Motherboard manufacturers competed furiously to be the first to get a PCI-E 3.0 board to market and there was even a minor scuffle between MSI and Gigabyte over whether their boards delivered true or fake PCI-E 3.0 technology. AMD is proudly stating it is the first to bring a PCI-E 3.0 card to the market in the form of the HD 7970 and as we know Intel was the first to bring a PCI-E 3.0 platform to the market in the form of Sandy Bridge-E and X79.

VR-Zone have been busy testing the HD 7970 on the Sandy Bridge-E platform in PCI-E 2.0 and PCI-E 3.0 mode and has come up with some unsurprising results. In a single GPU configuration PCI-E 3.0 and PCI-E 2.0 makes no different whatsoever with the PCI-E 2.0 run scoring X3219 3DMarks while the PCI-E 3.0 run scored X3212 3DMarks. Although multiple GPU configurations may reap benefits as we know with two or more PCI-E 2.0 GPUs having only 8X bandwidth can lead to a reduction in performance of about 5% and given the fact new PCI-E 3.0 cards will run faster and with greater bandwidth demand, the reduction would be greater on these models and so PCI-E 3.0 may be required.

Source: VR-Zone

  • Guest

    PCIe 2 to 3 changes the encoding scheme and CPU/PCIe bandwidth – therefore it will only help in CPU/PCIe bandwidth limited situations (as the latency is still the same). No games are CPU/PCIe bandwidth limited (all textures are usually preloaded), so the only things that do improve are in GPU Compute (science simulations) where it is needed. And that's exactly where certain websites found PCIe 3.0 did improve performance over PCIe 2.0 – in the pure compute. Some websites did pure gaming results and came to this conclusion.