Great pricing. Quad Intel i354 LAN. Dual Marvell SAS controllers (plus two onboard). ASUS iKVM
Only 2x DDR3 UDIMM slots
When we first heard of the ASUS P9A-I/C2550/SAS/4L we were admittedly excited. Here is a motherboard with a low power (14w) TDP Intel Atom C2550, quad gigabit Ethernet and onboard connectivity for up to 18 drives, all in a mITX package. Since we first published our preview article of the three ASUS Avoton motherboards weeks ago, we have been getting countless e-mails regarding the question of when they would arrive. Five days before my wedding, I got a note from ASUS that the ASUS P9A-I/C2550/SAS/4L hit North American shores and within 48 hours I was able to get one.
We used what is likely to be a common configuration for these platforms. Essentially, with the network and storage configurations afforded to the motherboard, this is being positioned as a cold storage platform.
- Motherboard/ Processor: ASUS P9A-I/C2550/SAS/4L with embedded Intel Atom C2550
- RAM: 2x 2GB Kingston ECC 1600MHz UDIMMs, 2x 4GB SK.Hynix ECC 1600MHz UDIMMs, 2x 8GB Micron ECC 1600MHz UDIMMs
- Storage: 16x Western Digital Red 4TB drives, 2x Seagate 600 Pro 256GB SSDs
- Power Supply: PicoPSU 150XT, Seasonic 650w (with hard drives)
- OS: Ubuntu 14.04 LTS, Windows Server 2012 R2, CentOS 6.5
We did not have a chance to run our full PCIe card suite with this platform due to time constraints but will do so later in July 2014.
The ASUS P9A-I/C2550/SAS/4L
Looking at the ASUS P9A-I/C2550/SAS/4L it is clear that the platform is very tight on space. The mini-ITX form factor allows for a 6.7″ x 6.7″ motherboard. The ASUS P9A-I platform has space for two full-length DDR3 DIMM slots. There are a rare few 16GB ECC UDIMM modules available so practically this is allows for 16GB of 1600MHz ECC memory in 2x 8GB configurations.
Before we get to all of the onboard components, the ASUS P9A-I platform also has a PCIe x8 slot that runs at PCIe 2.0 x4 electrical speeds. This is great since it does provide additional configuration options either for additional network or storage.
Next to the PCIe slot is a M.2 NGFF storage port for newer solid state disks. One should be cautious though as the M.2 connector is standard but the lengths of M.2 form factor drives are not. Our Crucial M550 128GB drive did not fit due to length for example.
The large heatsink just below the memory slots is for the processor. The ASUS P9A-I/C2550/SAS/4L uses an embedded Intel Atom C2550 processor with a 14w TDP. ASUS also has a similar SKU with the eight core Intel Atom C2750. Next to the small heatsink is a 4-pin CPU power connector and two SATA ports. One of the SATA III ports is disabled if the M.2 connector is used. In this area we can also see a total of six 4-pin fan headers which is plenty for this platform.
Likely one of the standout features of the ASUS P9A-I/C2550/SAS/4L are the dual Marvell 88SE9485 controllers. These controllers each have two SFF-8087 SAS connectors and can directly connect 8 SAS or SATA drives each. That means one has 16 SAS/ SATA ports, 1 SATA port and one SATA or M.2 port available for an easy path to connect up to 18 drives. These Marvell controllers are fairly popular but do consume 5.5w each.
In terms of the rear I/O panel there is a legacy VGA and two USB ports which is great for KVM carts or devices like a Lantronix Spider KVM. Next to this are LED status indicators and a physical power button. Atop of the USB 2.0 ports is a LAN port for the built-in iKVM solution.
Perhaps one the best design decitions for ASUS was the use of the Atom SoC’s i354 quad port gigabit Ethernet NIC. ASUS uses the Marvell 88E1543 PHY much like Supermicro solutions. The drivers for this configuration are the standard Intel drivers and the i354 is now well supported. The decision to use the Intel i354 and Marvell PHY is one that is a premium solution but is proven to work well.
In terms of performance, the ASUS P9A-I/C2550/SAS/4L was in-line with our Intel Atom C2550 benchmarks. We have the C2550 in our previous STHbench.sh test script archive and it will be part of the Linux-Bench.com archive in the next few weeks as that is rolled out. One can see some examples of the processor against cloud options in the new Amazon AWS EC2 t2 instance benchmarks.
The ASUS P9A-I/C2550/SAS/4L includes the ASMB7 management solution with provides features for remote monitoring and management. We did a deep-dive on the ASUS ASMB6 iKVM solution and it works very well. This motherboard has the next generation ASMB7 iKVM solution built-in. That ASMB6 article has much of the same functionality so it is a great place to get an overview of the ASUS management platform.
One management option that ASUS offers is ASWM Enterprise. We will do a full review of ASWM Enterprise in the near future. Here is a quick video on ASWM Enterprise:
Thermal Imaging and Power Consumption
For our thermal imaging tests we utilized our standard FLIR Ex series imager at 320×240 resolution with the MSX technology. This platform was extremely sensitive to power and our standard thermal testbed’s 650w Seasonic unit did not have enough load to start. We added a PicoPSU 150XT to the platform and everything worked well. One does need to be slightly careful not to oversize PSUs with these platforms.
Overall, results were excellent. All of the ICs stayed below required thermal limits. Just for fun, we did try cooling the system using 20db 40mm fans. This worked quite well and one fan on the CPU and another on the Marvell controllers managed to cool the system using 1.7w of power. In terms of power consumption, we saw a fairly 26.4w at idle using our Extech TrueRMS power meter (without drives.) During Linux-Bench multi-threaded runs we saw 30.2w maximum at peak. The platform benefits from having only two DIMMs but does have 11w of Marvell SAS controllers onboard.
Now for the really interesting part of the equation: price. ASUS sells the P9A-I/C2550/SAS/4L for $344. That is significantly less than buying a CPU, motherboard, 16 ports of SAS connectivity and a dual port NIC to augment onboard standard dual gigabit LAN. The other side to the equation is the operational costs which remain low due to power consumption. More DIMMs would have been good but there is no room for additional DIMM slots. Overall, this platform is going to be a strong contender for storage platforms especially with their low CPU requirements. It is certainly an interesting value proposition for those in the market for this class of embedded option and therefore receives very high marks.
This is certainly going to be a popular platform and we will give it an extended test when we get back from Bali!