Note: There is is an updated version of this page which may be found here. The pictures on the updated page are more detailed than this version, although the process is unchanged.
Click on any thumbnail image to view a larger picture.
Repairing a Sun NVRAM chip
The first step in repairing the NVRAM chip is to locate and remove the chip from the system. It can be identified ( usually ) by the orange bar-coded label on the top.
The second ext step is to grind away the DIP package on the end to reveal the power leads which join the top battery pack to the lower RAM chip. A "Dremel" tool or equivilent is handy, but a small grindstone in a drill will also work.
The third step is to remove the upper battery pack by inserting a sharp knife between the chip and battery pack and cutting through both ends. The battery back may be discarded.
The fourth step is to obtain a 3V Lithium battery and connect the battery to the exposed "pads" on the chip. Be sure to observe the correct polarity: the positive lead is on the top left side when the chip is oriented with the index ( Pin 1 ) in the lower right.
A bottom view of the completed chip. The fifth and final step is to re-Insert the chip into your workstation, being careful to orient the chip properly. Once complete, you will need to update the MAC address and HostId. If the original values aren't available,  you can find some useful information here.