The card from LSI Logic is not a low-profile type. The board itself is in fact rather massive. This is because its design is based on the six-channel controller (the MegaRAID SATA 150-6) from LSI Logic. The 4-channel model, which was enough for our purposes, contains some familiar components: two Silicon Image Sil3112s for the Serial ATA controller, 64 MB ECC SDRAM for the cache and an Intel GC80302 XOR processor. The latter differs from the GC80303 only in its memory interface speed - 66 MHz rather than 100 MHz.
The LSI Logic data sheet claims immediate array availability. This is true, for as soon as we had selected our options, we were able to access a drive under Windows. Initialization still needs to run in the background - a process that took over three hours in our tests. During this time, the array operates at a much reduced speed.
The performance of the LSI controller suffers under queue depths greater than 32, but its overall performance remains high. Ultimately, the MegaRAID SATA 150-4 manages to perform better than the Adaptec in most benchmarks.
It offers a range of features reminiscent of the Adaptec. FlexRAID is what LSI calls its ability to change RAID levels on the fly or to increase the capacity of the array by progressively swapping all of the drives. LSI's support focuses on Windows, Red Hat and SuSe, SCO Unix and also Netware.