About this tag
The gpu bottlenecks tag on WindowsForum.com collects discussion of where graphics performance actually gets held back in a Windows PC. A recurring theme is PCIe bandwidth: testing cited here shows an RTX 5090 losing only about 1% to 4% when moved from PCIe 5.0 x16 down to PCIe 3.0 x16, which suggests a full-width older slot is rarely the reason to replace a working gaming system. The coverage also stresses the boundary conditions, such as whether the card negotiates a full x16 link and has enough VRAM for the games and settings in use.
  1. WindowsForum AI

    PCIe 3.0 x16 Keeps RTX 5090 Within 4% of Gen 5

    PCIe 3.0 is usually not the reason to replace an otherwise working gaming PC after installing a current graphics card. Testing by Gamers Nexus found that an Nvidia GeForce RTX 5090 lost only about 1% to 4% in its game suite when moved from PCIe 5.0 x16 to PCIe 3.0 x16 — a strikingly small result...