|NETGEAR ReadyNAS NV+ v2 NAS Server|
|Reviews - Featured Reviews: Network|
|Written by Bruce Normann|
|Tuesday, 31 July 2012|
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Insider Details: ReadyNAS NV+ v2 NAS Server
The insides of these things are always more interesting than the outsides, at least to me. My first look inside is the drive bay, with three drive trays removed. The sturdy printed circuit board that acts as a backplane has lots of ventilation holes and a fair number of screws holding it in place. Both are indicative of good design, and probably lessons learned along the way. Inserting and removing the drive trays was smooth and positive, both with HDDs mounted in the trays and without. The smooth surfaces and heavy plating on the metal parts was a helpful factor, I'm sure. The latches acted like a locking lever; once the trays reached the end of their travel, swinging the latch down levered the tray into firm contact. All in all, a nice, sturdy, well designed system for getting the drives in and out. Not that you want to take them out very often, maybe just for spring cleaning once a year!
Once you take a screwdriver to the chassis, it comes apart in several smaller pieces. Each of the sides, the top and the bottom has their own panel. In addition to their decorative function, they each add some portion of rigidity to the overall structure. All the panels are steel, so there's very little flexing going on, once everything is bolted together tightly. The rear panel comes off with the cooling fan attached, a 92mm unit that's 25mm thick, branded MAGIC, and spins at approximately 3500 RPM when it gets full voltage. Specs were hard to come by, so that's just an estimate, but judging from the fan speed display on the ReadyNAS Dashboard S/W, its close. At idle, the Dashboard utility indicated a fan speed of ~1100 RPM, with the drives running at temperatures ranging from 40C - 42C.
The main controller PC board is firmly attached to a steel tray of its own, and it slides into the chassis at the very top of the unit. The tray is not held in place by screws, but is captured by the mating panels which leave it with no room to move. The upper and lower drive bay guides are held in place by a number of rivets, ensuring that the inner frame is quite stiff and dimensionally stable. Honestly, this thing is built like a brick, mechanically at least. I can see a large number of areas where it would have been very easy to reduce costs in the mechanical package. I don't know what the original ReadyNAS NV+ looked like, but I'm betting it was built pretty much the same. In today's economy, it would have been too tempting to cut a few dozen corners on a new design, particularly for a product that's not geared toward a data center environment.
The main controller board and backplane connect with a PCI Express connector located toward the rear of the controller card, between the CPU heatsink and the stacked I/O connector. A couple of construction details to notice: the grounding pads on the backplane that mate up with the chassis mounting points, the lack of any active components on the backplane, and the use of a separate PC board for the front panel controls. The heatsink is a very meager affair, and it serves two chips, the Marvell 88F6282 CPU and the Marvell 88SM4140 SATA port multiplier. These two chips do the bulk of the work for this device; the only other chips that are stressed are the memory and the Ethernet controller. I suppose the USB 3.0 chip could get a workout, but only if you have an external drive with an SSD attached to it. Anything else wouldn't put too much strain on it.
The limited cooling required for the two hardest working chips on the controller board is made even more obvious once you remove the heatsink and see the type of thermal interface materials in use. The CPU is thermally connected to the heatsink with that hard, plasticky material that we used to see on low-end video cards in the '80s and '90s. At least the assembly process and the viscosity of the material worked together to produce a thin interface layer. That's better than a 1mm thick layer of the good stuff, perhaps. The port multiplier gets a silicone pad, partly due to the need to make up the height difference between the two chips. Neither chip is working too hard, apparently. We'll see the result of their work ethic once we start testing throughput of the entire NAS. The CPU is readily available in 1.6, 1.8, and 2.0 GHz versions, and I do wonder how much the cost is reduced by using the slowest version of the chip.
Speaking of cooling - I know I mentioned the fan before, but here it is mounted to the rear panel with the traditional, stubby, thread-forming screws that 90% of PC case fans are fastened with. It's a standard 92mm case fan, with 3-wire tachometer control and is heavily modulated by the controller card. The foam and mesh composite shielding gasket surrounds the USB 3.0 and RJ-45 Ethernet connectors. That's where the high speed data path is, and it looks well protected from RFI. Good grounding practices were also in evidence throughout the construction of the rest of the chassis. Even though I didn't point them out in every image, most of them contain at least one feature that was put there specifically to improve grounding paths and to create a stable RF shield around the entire package.
So far we've had a good look at what there is to observe as far as hardware goes, but let's dig down one more layer, down to the chip level where the technology really starts to get interesting. I love my shiny hardware just as much as the next person, but it's only half the story....