Internals, Testing Methodology and System Setup
First a look at the outside:
Brackets were removed for these pictures as we were into partial disassembly at that point. I included a pair of P3700's along side the P3608 to emphasize the fact that the contents of *both* of the single units (left) has been effectively combined into the *single* package of the P3608 (right). This is no small feat.
Once disassembled we note that Intel opted to include a back plate on the P3608. They have also been shipping SSD 750's with this same type of plate, so it seems all future HHHL SSD products fromthem will include such a plate.
In the following two pictures I will place the P3608 on top of a similarly oriented P3700 for comparison of the layouts:
Right away we see that there are two controllers on the P3608, along with an additional PLX chip (more on that later). Also noteworthy is that there are far less flash memory packages present on this side of the P3608. Let's check the back:
There are also far less packages at the rear. With half the number of packages and double the available capacity, it's no wonder we noted the oddly decreasing random write specs at higher capacities, as Intel would only be able to stack these dies so high within each package and therefore could only offer a 4TB capacity (nearly 256GB per flash package works out to 16-die stacks!) by dialing back the overprovisioning, which translates to reduced random write performance of those higher capacity models.
This is where the magic happens. The PLX PEX8718 is a 16 lane PCIe 3.0 switch that funnels data from both of the PCIe 3.0 x4 controllers to the host over a PCIe 3.0 x8 link. This is a smaller version of the same sort of PCIe switch that enables two GPUs on a single graphics card. For those wanting to geek out further, the data sheet for this particular chip is available at Mouser.
This is our first review using a purpose-build enterprise testing suite. We will cover the methodology further into the review and welcome your feedback on our process and presentation.
Test System Setup
We have several storage testbeds, but for this piece we used the same setup used in our 5-way SSD 750 RAID testing. It is not server-class hardware, but it is a reasonable equivalent that allows us to push the CPU to higher clock speeds than server hardware would normally be capable of. This helps shift the burden / bottlenecks to the NVMe PCIe SSDs under test.
PC Perspective would like to thank Intel, ASUS, Corsair, Kingston, and EVGA for supplying some of the components of our test rigs.
|Hard Drive Test System Setup|
|CPU||Intel Core i7 5960 @ 4.5 GHz|
|Motherboard||ASUS X99 Deluxe|
|Memory||16GB Micron DDR4 @ 3333|
|Hard Drive||G.Skill 32GB SLC SSD|
|Video Card||GeForce 210|
|Power Supply||Corsair CMPSU-650TX|
|Operating System||Windows 8.1 Pro X64 (update)|
- PCPer Enterprise Storage Test Suite 0.9 (beta)