- A simple way to add fast SATA drive hot-swap capability to a tower case
- Limited mounting options may present problems with some computer cases
- Adds two fans
One of the design advantages of the SATA hard drive interface over the preceding PATA/E-IDE interface is the ability to hot-swap. However, to take advantage of this feature a computer must be fitted with a suitable mechanical mount to allow the SATA drives to be inserted or ejected easily. The Axstor AX-DC-3 (£89 ex. VAT) and AX-DC-4 (£99 ex. VAT) SATA drive cages provide hot-swap mounting for three drives in the space of two 5.25in. bays, or four drives in the space of three 5.25in. bays, respectively.
In use, individual drives are inserted or removed by lifting a small latch to release a gate that closes over the front of the drive and holds it in place. The gate can then be swung open about a hinge on its right-hand end. As the gate is opened, a mechanical link operates an eject lever at the back of the drive that pushes the drive forwards and decouples it from the SATA connector mounted in the backplate of the cage. These connectors are back-to-back couplers, with the socket inside the cage extending directly into a plug emerging from a slot in the outside face of the cage back panel. Both the connectors and the drive ejection mechanism are rated at up to 50,000 insertions.
The Axstor design is caddy free; there's no separate protective sleeve that needs to be fitted to each drive before insertion. Each naked drive simply slides in and is supported along each edge by channels in the sides of the cage. Although this keeps things simple and makes for the fastest possible drive replacement, it does mean that drives that are regularly swapped in and out need to be handled and stored with a little extra care when they're not in the cage.
The Axstor AX-DC-3 drive 'cage' is actually a closed box, with two extruded aluminium sides, finished in a matte silver anodising and sheet steel panels for the top and bottom, finished in a fine black crackle enamel. The back and the front, with the three hinged gates, are made of black plastic.There are two 35mm cooling fans mounted on the back panel and these are powered via a separate 4-pin AMP power connector, also mounted on the back panel. There is a 6-way DIL connector next to the fan power connector that can be used to connect to three individual drive activity indicator LEDs mounted on the front panel.
Provided with the AX-DC-3 are a four-way power splitter cable for connecting fan power and three combo SATA power and data cables for connection to the three power/data plugs at the back of cage. Each combo cable has a one-piece SATA power/data connector on one end, plus a short, two-way jumper cable that connects to two of the pins on the 6-way DIL, for LED indication of drive status if required. Cables from this combined connector then split out into a data cable terminating in a SATA data connector and into a four-way standard AMP power socket. Separate data and power cables would perhaps be more useful, since most power supplies today come with several outputs terminating in SATA power connectors that can be directly connected to the power section of the plugs on the cage, although this would mean that the LED indicators remain unconnected. Four mounting screws are also provided.
The two aluminium side extrusions of the Axstor AX-DC-3 are pierced by a total of four M3 threaded holes, two on each side. These are intended to be used to secure the AX-DC-3 in place inside the drive bay frame of the host PC case. Unfortunately they turn out to be a slight design flaw because many tool-free case designs rely on there being a pattern of four fixing holes on each side of each drive to accept the clip in drive rails, so fitting the AX-DC cages to some cases could prove troublesome. On our test system we had to modify the drive rails to mount the AX-DC-3 in the bays.
The Axstor AX-DC-3 and AX-DC-4 SATA drive cages are ideal for quick and easy maintainence of critical RAID systems, for disc cloning, for systems using hard disks for rapid backup or for test systems that are required to run mutiple test environments. Multiple Axstor cages can be mounted to cater for more than four drives.