Building an inexpensive 16-CPU 128GB home server (Part 1)

Intel just released their latest desktop processor, the Core i7–6950X. This CPU is clocked at 3.0HGz — 3.5GHz, with a 25MB cache, and 10 cores supporting hyperthreading. It also supports 40 PCIe 3 lanes, and 4 x DDR2400 channels. The reviews are in on Anandtech and Ars Technica, but the standout feature for me on this CPU is the wallet-lightening price tag of $1749.99 on Newegg. If you needed evidence the lack of competition in the x86 CPU market is hurting consumers, this is a good start.

Fortunately, if you’re in the market for a high-CPU-core machine, you can build a complete 128GB 16-core server-class system for less than $1299.99. This is exactly what I did for the last couple of weeks, and have written up all the information below. Read on to find out all the details !

CPU and Memory

This story starts off with the venerable Intel Xeon E5-2670 v1 processor. Introduced in Q1 2012, it’s clocked at 2.6GHz — 3.3GHz, with a 20MB cache, and 8 cores with hyperthreading. Each CPU has 40 PCIe 3 lanes, with memory support up to DDR3–1600 (PC3–12800). They also support 8GT/s QPI, which along with Symmetric Multi-Processing (SMP) means you can use it in a dual CPU setup. This CPU was bought in huge quantities for servers by all the major internet companies when it was first released.

These same internet companies are now decommisioning those servers, as the E5-2670 v1 CPUs are officially end-of-life, and Intel is up to v3 of the E5–2670. This means supplies of decommissioned E5–2670 v1 CPUs are now flooding the second-hand market in huge quantities, driving their price down.

NATEX is an online retailer specializing in end-of-life reselling of server and desktop computer components. They’re selling Xeon E5–2670 v1 CPUs for $65.00. That’s not a typo! At that price it would be rude not to pick up 2 of them. So for $130 you get 16 cores, 40MB of cache, and 80x PCIe 3 lanes.

As well as CPUs, NATEX also sell decommissioned server memory. Kits of PC3–12800R 128GB RAM are available for $240.00 each. These are the fastest RAM modules the E5–2670 v1 supports. Just bear in mind that to use this RAM you’ll need a motherboard with 16 RAM slots.

Motherboard and Hard Drive

The Xeon E5–2670 v1 uses the LGA2011 socket (which is now superseded by the LGA2011–3 used by v3 Xeons and higher). Dual LGA2011 CPU motherboards with the X79 chipset are available with up to 16 RAM slots, and support multiple PCIe 16x cards.

ASRock makes affordably priced Dual-CPU motherboards with the X79 chipset. They’re regularly sold out on Newegg, when last in stock the E2C602–4L/D16 motherboard sold for $329.99. This motherboard is an SSI EEB sized-board, and has 16 DDR3-1866 RAM slots, dual LGA2011 CPU sockets, and 4 PCIe 16x.

Keeping things affordable, the Samsung EVO 500GB SSD is only $149.99 with good performance and a great price tag.

Case, CPU Cooler, and Power Supply

For a powerful system with 2 x 115W TDP processors, you’ll need a large case with 140mm diameter fans to keep everything cool. The Fractal Design XL R2 is $129.99, with those fans spinning slowly to keep things cool and quiet. The case has great cable routing and supports a number of vent configurations.

CPU Coolers can be some of the noisiest parts of a high-TDP build. Many large radiator-based coolers are available nowadays though, with one of the best performing ones being the Noctua NH-U12DXi4. These retail for $69.99 ($5 more than the Xeon processors!) and you’ll need one for each CPU for best performance. So for both coolers its a grand total of $2 x 69.99 = $139.98.

The PSU for the build needs to support 2 x 8-pin connectors in addition to the 24-pin ATX power connector. Not all PSUs have 2 of the 8-pin connectors, and having headroom for future GPU cards is a good idea. I chose the Corsair RM1000X 1000W PSU. This runs in a fanless mode up to 400W, and has 2 x 8-pin connectors.

Wrapping it all up

Now you’ve seen the list of components, CPUs, and the case it’s time to total up the cost of this build. All the prices are based on my invoices from the start of May 2016, and prices and availability may have changed in the meantime.

  • Asrock EP2C602–4L/D16 — $329.99
  • Hynix 128GB 16x8GB PC3–12800R — $240.00
  • 2 x Intel Xeon E5–2670 SR0KX — $130.00
  • 2 x Noctua NH-U12DXi4 CPU coolers — $139.98
  • Samsung 850 EVO 2.5" SSD — $149.99
  • Fractal Design Define XL R2 case — $129.99
  • Corsair RM1000X 1000W PSU — $159.99

This comes out to a total of $1279.94. For an entire system. That’s $470.05 less than the new Core i7–6950X.

UPDATE: I wrote up a description of the build process, the issues I had keeping everything cool, and other tips that will be useful it you’re thinking of building your own machine. Click through to Part Two to find out more!

UPDATE 2: Natex now offer an entire pre-built system which is almost identical to this machine, but only costs $875. It includes everything apart from storage, so you’ll need to buy your own SSDs or HDDs. They use the Intel S2600CP2J motherboard, which has the same chipset as the ASRock one I went for. If you don’t want the hassle of building yourself and want to save some money this is a great option.