Quote Originally Posted by harhow View Post
Apparently the BIOS is stored in the DS12887A and of course the new one does not have it.
The DS12887A is a RTC, it is not the BIOS. The BIOS chip is elsewhere on the motherboard.

If you replaced the chip and nothing works, make sure that you got a new DS12887A and not new-old-stock where the chip has been sitting around for decades and the battery went flat. Also make sure that you don't have a counterfeit relabelled chip, which is also very common.

The date code is printed on the face of the chip under where it says "REAL TIME" There will be a string of four numbers followed by one or two letters/numbers.

An example is the following:

0813DV - Week 13 of 2008.