After receiving a SuperMicro 750-A case I thought, "wow, now this is
a case!" Thinking the 750-S would be just as good, I ordered one to
replace an older case. Alas, the 750-S is quite a disappointment
compared to the 750-A. It's like a cheap half-hearted immitation of
1. Where the 750-A has three rows of air inlet slots on each side
of the case adjacent to the drive bays, the 750-S has only one
2. The drive rails block what little air might be pulled in or
pushed out through those slots.
3. The rear exhaust fan in the 750-A is a 4-inch (120mm) fan. It's
a 3-inch (80mm) fan in the 750-S.
4. In the 750-A both the auxilliary fan and an internal 3-1/2" drive
cage can be mounted at just about any position on two separate
sets of slide rails. The 750-S has just two fixed positions.
You can swap 'em or remove 'em, but that's it.
5. I seem to have been shorted on plastic snap-on fan mounting
enclosures. My 750-A came with seven (7) of them. The 750-S
came with only four (4).
6. The motherboard mounting plate is removable, but only by removing
a zillion screws. With that in mind, it doesn't appear to have
been designed to be removed. Of course, it's not removable at all
under any circunstances in the 750-A, so although this is an
additional disappointment, it's not any worse than the 750-A.
Mind you, compared to my old case, the 750-S is still much better.
Even with its shortcommings, the 750-S makes much better use of
the available space. It's also light years ahead in the airflow
department. It was also less expensive than my old case (purchased
four years ago at that).