Sunday 11 January 2015

Enermax EMK5402 And EMK5201U3 Mobile Drive Racks

Enermax EMK5201U3

Mark looks at a couple of mobile rack solutions from Enermax

Having external drive bays can be exceptionally useful. It allows you to use bare disks as portable storage and also enables you to quickly swap out drives for testing and cloning. As a reviewer, I used these things daily, but the requirement isn't anything that is exclusively of interest to journalists.

With the rise of the SSD, we're all using many more 2.5" sized devices, even in desktop systems. And both these two products from Enermax acknowledge those changes with the inclusion of support for the 2.5" form factor.


I'll say up front, one of these designs I liked, while the other managed to irk me before I'd finished with it. Let's start with the EMK5402 before moving on to its brother, the EMK5201U3.

The compact EMK5402 contains room for no less than four 2.5" drive mechanisms, in a single half-height external drive bay. To that end, there are four SATA ports on the back corresponding to each bay and two Molex power connectors supporting the four potential drives.

Why these use Molex and not SATA power connectors I'm unsure, but most systems still have both, so it shouldn't be an issue. It also has two 35mm fans, providing some airflow through all the bays.

Each bay can be individually locked and has an activity LED to show the drive is in use. What's critical to understand if you intend to use something like this is that these bays aren't intrinsically 'hot swap', unless you set the SATA port it's connected to as being 'removable' in the BIOS.

Initially, I thought this was an excellent product that solved the clutter problem I'd personally experienced with SSD testing recently. But then I realised that EMK5402 has a big flaw, in respect of the disk ejection system.

Enermax EMK5402

Instead of applying pressure to the sides of the edge connector, it instead applies it to the narrow surface directly above the connector. That is fine if the drive is 12.5mm, and it might even work if it's 9.5mm deep, but can miss the drive entirely if it's only 7mm thick. That's a shame, because that's the thickness that most SSDs are turning up these days, and they're unlikely to get thicker any time soon.

The result of this is that I've just sent a lovely SSD back to Samsung with a lovely scratch, because when I tried to eject it, the drive stayed put and the drive gouged its surface instead.

What I found most annoying about this was that the identical problem addressed differently in the EMK5201U3 copes with any drive thickness perfectly.

In only copying with two drives, one each of 2.5" and 3.5", theEMK5201U3 is somewhat less ambitious in its use of the half height space but generally more successful.

The two drives are serviced by a single SATA power cable, but you can convert it to using two if you're concerned your drives will demand too much power.

They each have their own SATA data cable, so they can run attached drives at the full 6Gbps specification. As an added bonus, Enermax also included two front-facing USB ports that have the cabling to be attached to a 20-pin motherboard header. And unlike the EMK5402, all size drives eject smoothly from this design.

One extra feature I also really liked was that it has a little power on off switch, which could be a boon for those who like to dual boot but don't like to install menus. It's also a much better solution for those who want to use eSATA for detaching/attaching storage while the system is running.

If this equipment has a weakness, it's that Enermax isolated the drive bays from its side mountings using vibration dampers. These allow plenty of movement, so you need to use all eight screws, four each side, to attach it to the case, or it will twist when you try to eject drives and push them home. It's rated for 50,000 drive exchanges over its life, so once secured to the case it should be fine.

It also doesn't have a fan, though the 3.5 slot is open underneath, so it should get some ventilation if you position it in a bay that hasn't a solid floor.

Other than those minor issues, this is a very serviceable design and one that, when coupled with Enermax's own EMK3104 converter, can easily cope with dual 2.5" drives.

For the problems I've mentioned and its rather high price, I'd avoid the EMK5402, but the EMK5201U3 is certainly worth considering if you have a system where you're continually changing drives of either size standard. It's also much more realistically priced. Mark Pickavance