eisa controler

I am running win 98 second edition. In device manager I have a explanation mark on “EISA direct memory access controller”
upon selecting “properties” it states that
“VDMAD.VXD device loader(s)for this decive could not load the device driver(code2) to fix this, click update drive to update the device driver”.
However windows tells me that the best driver is already installed.
Help on what VDMAD is and how can I find right driver.