Default Versus Maximum Performance Mode
The Intel SSD 910 offers two performance modes for the 800 GB SKU; Default and Maximum Performance.
|User Capacity||800 GB||800 GB|
|Interface||PCIe 2.0 x8, Half-Height, Half-Length|
|Sequential Read||2 GB/s||2 GB/s|
|Sequential Write||1 GB/s||1.5 GB/s|
|4K Random Read||180 000 IOPS||180 000 IOPS|
|4K Random Write||75 000 IOPS||75 000 IOPS|
|Power Consumption (Active)||<25 W||28 W (38 W Max)|
|Power Consumption (Idle)||12 W||12 W|
|Required Airlfow||200 LFM||300 LFM|
|Write Endurance||14 PB||14 PB|
Intel refers to each storage controller and its corresponding 200 GB of user-accessible flash memory as a module. In Default mode, each of the two or four NAND modules is throttled to make sure that the total device power falls within the PCIe power specification's envelope. In Maximum Performance mode, any two NAND modules can be accessed at full speed and still be considered PCIe-compliant. Stressing all four NAND modules in Maximum Performance mode violates the PCIe specification, and may cause trouble in some systems.
As you can see in the image above, the power dissipation limit for a PCI Express x4 or x8 card is 25 W. Maximum Performance mode is specified by Intel to top out at 38 W, though. Now, will your specific server drive this device correctly without a compatibility problem? It should. But you'll certainly want to check with your server vendor to be sure. We dropped the SSD 910 into a half-dozen systems and didn't run into trouble with any of them.
More concerning is the amount of airflow required in Maximum Performance mode. The base requirement of 200 Linear Feet per Minute (LFM) is fairly common for server-oriented add-in cards. Bumping up to 300 LFM might be a challenge in servers with adjacent cards installed, especially if those cards are also PCIe-based SSDs or high-powered RAID cards.
We do appreciate the fact that Intel allows for this option, and that the company is very clear about the implications of enabling it. If you are concerned about power and cooling (enterprise customers should be), check out the performance results in Default mode first.