"NVIDIA nForce PCI System Management" is neither a model number nor a nVidia chipset number.... one of which is required to help you. I addition, a driver request should always include the computer/motherboard information (ie: brand and model).
If you are unable to properly identify your hardware, open Device Manager, double-click the device, click the Details tab and give me the hardware ID string. It should start with PCI\VEN......... eg: the first line of text.
Is this a PCI card as stated or is it actually integrated on the motherboard?