douglar wrote on 2024-04-13, 11:00:

Here is the correct photo of the 16 chip DIMM--

Samsung K6S280832a-TC1L - 4 bank PAGE BURST - 16Mx8bit

I'm surprised that it worked on the EX board and the BX board.

Now, it is no surprise that this module works. You are no longer dealing with single-rank modules. This is a dual-rank module, each rank has 64 bits, so using x8 chips, it consists of 8 chips. A 256MB module with two ranks has 128MB per rank, which is the upper limit of the 440BX chipset. Another way to express 128MB per rank is to talk about 16M words of 64 bits (8 bytes), and this is the actual limitation of the BX: The maximum number of addresses supported on a rank is 16M - and that's exactly what your Samsung chips provide.