MSI Mode (and its successor MSI-X) allows devices to write a message directly to a special address in the CPU’s memory. Every device gets its own unique interrupt vector. The result is lower, more consistent latency.
The MSI Mode Utility v2 (or v3) is a 500KB executable that solves a problem Microsoft should have fixed a decade ago. If you are chasing the lowest DPC latency for gaming or audio production, this tool is essential. msi mode utility v2 download