I have an Adaptec 6805 card with 4 - 2TB drives and 4 - 4TB drives. I made them into two logical RAID 10 drives and in the past two years, I have had 3 instances of Windows Server 2012 giving a BSOD. Each time, the arrays still showed optimal but Windows Server showed them as RAW drives. Would a situation such as a BSOD be remedied by having one of these Flash Modules?

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Possibly. The purpose of this "ZMM" flash module is write cache control. In the event of a power outage, if there is outstanding data in the controller's memory waiting to be written to disk, the capacitor in this device is supposed to provide enough power to save that data in the flash memory instead. That way when power comes back on, this data can be retrieved from flash and permanently written to the disk, avoiding data corruption.

My advice is that you should not enable the controller to do write caching unless you have installed this device. That way you won't chance losing data from a power outage. However, in my testing, disabling write caching caused write speeds to plummet from about ~120 MB/s to ~20 MB/s. Therefore, I simply cannot recommend the Adaptec 6805 controller without this ZMM flash module and enabling write caching on the controller.

In order for this device to work correctly, you must enable write caching at the controller level, but _disable_ it for the individual physical disks, since the flash module can only save the data that's awaiting writing by the controller. If you have write caching enabled at the disk level and there's a power outage, the ZMM won't do any good.

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