According to the release notes, the new Geforce 465.89 Game Ready driver update includes optimizations for DiRT 5 raytracing update, Evil Genius 2: World Domination, and Kingdom Hearts series on Epic Games Store games. It also includes support for OpenCL 3.02 API, adds SLI support for Shenmue III and The Medium games on Turing GPUs, as well as fixes numerous bugs.
The biggest update is support for the Resizable BAR on GeForce RTX 30-series desktop and mobile GPUs, as well as beta support for virtualization on Geforce GPUs.
There are a few drawbacks, as you need to update the vBIOS in order to enable PCIe Resizable BAR, via either the Nvidia site if you are running the Founders Edition card or from a specific Nvidia AIC partner. Of course, you also need a supported motherboard.
According to Nvidia, ReBAR is supported in 17 titles so far, and you are looking at anywhere between 5.9 and 11.9 percent performance improvement.
You can check out more details and instructions for ReBAR support over at Nvidia, and find the latest driver as well as full release notes over at Nvidia's driver page.