The exact locations are here:
http://www.nvidia.com/object/nforce_nf4_winxp_6.39 (Win XP)
http://www.nvidia.com/object/nforce_nf4_win2k_6.39 (Win 2K)
Version: 6.39
Release Date: February 4, 2005
Installation Notes
Windows XP users must install Service Pack 1, at a minimum, prior to attempting to install this package. Failure to do so will result in the inability to support USB 2.0.
Installation of DirectX 9.0 or higher is required in order to use NVMixer.
Release Notes
WHQL-certified kit
Standalone drivers with support for nForce4 products, including support for dual-processor systems.
Added support for NVIDIA Disk Alert System
General compatibility fixes
Windows XP/2000 Driver Versions
Audio driver 4.60 (WHQL)
Audio utilities 4.51
Ethernet driver 4.68 (WHQL)
SMBus driver 4.45 (WHQL)
Installer 4.60
IDE NVIDIA driver 5.07 (WHQL)