There a re lot of different modules for the ESX-2400 and ESX-4800 series.

For first, the mainbard (the switch fabric) is the same for all units. All 4800 and some 2400 boards have DC to DC power units on board, some (2400) are supplied from external power supplies, depending on the revision.

There are 4 special connectors for the two daughterboards.

These connectors are from the same high quality than the backplane connectors. The modularity ranges from 6 x 1Gigabit/s to 48 x 10/100 Mbit/s modules.
There is a mix of the two sizes and all versions for many combinations.

Here you see the two 3 x one Gigabit fiberoptics daughterboards from a 4800. Both have the same functionality but different size.
We will add some tables, what models have been available and what spare part numbers have been assigned.