Computer Hardware

Computer systems that run the telescopes, store data, and provide remote analysis for users are currently built in house from standard components selected for the best performance/price ratio. The selections here were updated in Fall 2014. Typically useful lifetimes for hardware before failure or obsolescence is 3 to 5 years.

Servers

The Supermicro 823TQ-653LPB is a 2U rack server that accommodates 6 hot-swap SATA drives and 1 full height DVD. It includes a single 400 watt power supply.

This and other 4U servers are available from Servers Direct assembled with motherboard and processor of choice.

Workstation Chassis

Corsair Obsidian Series Black 550D Mid Tower Computer Case $117

Corsair Mid Tower case on Amazon.com

A large case provides exceptional ventilation, ease of access, and quiet operation. USB3 is brought out to the front panel. The interior has many slots for SATA drives and for two full height DVD drives. If rack mounting is not required, it will work splendidly as a server enclosure especially for systems with GPU cards that require high power. The SATA drive carriers do not use screws, and while the drives are not hot swappable, it takes only minutes to replace one without tools.

Alternatively, for Supermicro motherboards their mid-tower chassis is smaller and comes with a power supply for about $130:

Supermicro SC732i-500B mid-tower chassis

Power

The Corsair power supplies have been reliable and are quiet. A typical one is the CX600 available for about $66.

Corsair CX600 on Amazon

Power supplies for the observatories have to be quiet, and should be green with high efficiency. Typical lifetimes have been 3 to 5 years, but some supplies from Antec have had premature failure and are not recommended.

CPU

The best CPU is selected at time of purchase based on price, availability, and Passmark ratings from this site:

http://www.cpubenchmark.net/

As of November 2014 the preferred solution is a Xeon E5-2620 V3 6-core LGA2011-V3 socket CPU running at 2.4 GHz and 85 W with a Passmark rating of 10,743. It is available from Amazon for $446.

These boxed CPU's are supplied without a cooler which is purchased separately. We use the low cost air-cooled Intel Thermal Solution Air $36 The cooler runs quietly, and is not at risk for use at a telescope where there may be temperature extremes.

Motherboard

We have had good success with motherboards from Supermicro. Currently there are more than 10 in service, some for two years of continuous use. We have had three failures in two years. One was in a system exposed to environmental extremes, and a similar one was in a controlled environment. Both failed after a power disruption even though they were on surge-protected circuitry. The problem could have been with the motherboard itself, or due to a spike from the power supply. We have not had a failure with the preferred power supply noted below. With any case and a recent motherboard it is necessary to check that the supporting stubs match the available holes and that there are no unused stubs without a matching hole.

Supermicro X9SRA Xeon and I7 supports 512 GB of DDR3 memory in 8 sockets, and offers 2x PCI-E 3.0 x16, 1x PCI-E 3.0 x4 (in x8), 1x PCI-E 2.0 x4 (in x8), and 1x PCI-32. It is available through distributors offered by Amazon for about $275. This board has built-in audio, no video, 4 USB 3.0 ports and 8 USB 2.0 ports from the rear of the chassis, plus 2 serial ports on a header.

The newer Xeon E5-2600 systems require a different socket, and the Supermicro X10SRL-F is preferred.

Memory

For the current Xeon E5-2600 processors, the LGA2011 socket motherboard requires 2x or more 8 GB registered ECC DDR4 modules. Crucial memory costs approximately $260 for 16 GB.

DDR4 ECC

There is a requirement to use non-ECC memory with I7 processors but when upgrading computers at telescopes we are switching to Xeon processors with ECC.

Hard Disk Drives

All new drives are Seagate Enterprise (formerly Constellation) class SATA drives.

The 4 TB drive now at $256 on Amazon would be the cost effective choice over a 6 TB drive for new installations in 2014:

Seagate Enterprise Capacity v.4 4TB SATA ST4000

Note that the commodity Seagate Barracuda line is not as reliable and has had in our uses an MTBF of about 2 years. We have not had a Constellation drive failure since implementing them in 2012.