ASUS officially lists drivers up to Windows 8. For Windows 10 or 11, many drivers (like audio and chipset) may be automatically installed via Windows Update. However, specialized hardware like the NVIDIA GPU or certain Function (Fn) keys might require manual installation using Windows 7 or 8 drivers in "Compatibility Mode".
Go to ASUS.com → Support → Drivers & Manuals → Search for “K43S” . asus k43s drivers
Before any driver change, search for "Create a restore point" in Windows. Name it "Before K43S Driver Update". ASUS officially lists drivers up to Windows 8