well, i'm here to report back that Supermicro's cable management arm is completely, and utterly useless. For the benefit of anyone in the future who might stumble on this thread searching for information about Supermicro's cable management arm: do not buy it - it's a product that probably has never been field tested.
as i suspected, the cable arm comes way too close to the rear of the chassis. when i attempted to actually run cables, almost nothing worked. the only cables I could get to work are power and network to the onboard NICs. what won't work at all are:
- VGA/KVM cables - not even remotely close and if you force it, you'll likely break the VGA connector off the motherboard.
- any network cables to the PCI slot area - the arm is extremely close here. if you can run towards the left (looking at the back), you might have enough room hence the onboard NICs are probably okay, but it is still a very tight fit.
- SFP+ and optical cables - definitely no. SFP+ modules would stick out too much, and any LC connectors would require a bend radius that is way too much.
On top of all this, the arm is too long and extends almost all the way across the width of the rack. So, this means, with the arm in place, you cannot pull out the PSUs. If you had to, you would need to disassemble the arm from the brackets, which would risk pulling out power cords if you are trying to hot swap a failed PSU while keeping the system live.
I had considered adding a fabricated bracket to push the arm towards the back of the rack to add more clearance for the cables, but when I realized the width of the arm obstructs the ability to remove the PSUs, it just isn't worth the effort. This just seems like a product that was designed in some CAD program and never actually tried in the field.
This product (
MCP-290-00073-0N) is a total failure. Don't waste your money on it.
So, this basically has me concluding that having a useful cable management solution for the rear side of the server so that one can do maintenance on systems without having to unplug cables is non-existent for Supermicro systems. I'm a bit sad about this fact, knowing HP and Dell have this type of stuff pretty much figured out and I was starting to become a Supermicro fan. Anyway, I'm abandoning this effort and going to look at ways to support the cables with horizontal cable management rack accessories. I'll just have to deal with having to unplug everything first whenever I need to pull the server out of the rack.