We have three Icy Dock MB996SP-6SB backplane systems here now for our dual Xeon NAS load system. While Intel tracks down the Xeon processors for us, we went ahead and build two systems to run our new advanced NAS load program.
Each system is a model for high density computing, running 12 Hyper-V installs of Windows 7 in a 4U Antec Take-4. The Antec Take-4 case is perfect model for showing off the MB996SP-6SB because it first hit the market before the 2.5" form factor entered the enterprise or power user market. There isn't a single 2.5" bay in the case.
Getting back to business, remember the warning sticker that says only use the supplied screws with the MB996SP-6SB? Here we see the screws, they are very small, but if your case is made out of paper you won't have a problem getting a thread and a half from the screw into the MB996SP-6SB.
Let's do the math real quick. You have two 2.5" drives going into a 5.25" space. That leaves around a quarter of an inch available, but you also have a few buffers tossed in the mix as well, like the sides of the MB996SP-6SB and the sides of the drive sled. That doesn't leave a lot of room for things like screws.
In the image above we see the silver Corsair Performance III drives through the mounting holes. The drives are right next to the side of the case and because of this you can't use long screws in the holes towards the front of the drive cage.
Here we see the micro screw sticking out of the 5.25" cage. I'd say the Antec Take-4's metal is about average in thickness for a case. You get about half to three quarter of a thread to secure your cage in the case.
I wasn't able to get the supplied screws to bite into the MB996SP-6SB so I just used regular fine thread screws in the back four (two on each side) mounting points. I couldn't use the same length screws in the front mounting points because they hit the SSDs. I would have liked to see Icy Dock ship screws that were about 2mm longer than the current screws that ship with the system.
I also tried the screws in a few other cases and none of my test systems that used screws would work with the supplied hardware. My screwless systems worked fine though.