HighPoint's RocketRAID 1640 relies on its own well-known HPT374 RAID controller, which implements RAID 5 in software only. In fact, this component is an Ultra ATA device fitted with Serial ATA bridge chips made by Marvell.
This does not necessarily mean that performance will suffer, as you can see from the test results, where the RocketRAID 1640 is clearly superior to native Serial ATA controllers in some respects.
Like Adaptec, HighPoint favors the low-profile format. However, its suitability for use in a rack-mount environment is somewhat limited by the way the connections have been implemented - unless you are prepared to apply brute force to the cables.
The HighPoint controller has the edge when it comes to setting up a RAID 5 array: in contrast to most of its competition, we were able to construct an array in a record-breaking 14 minutes. The Promise finished faster, as it was the only one that did not carry out verification.
We were impressed with HighPoint's software support. As well as drivers for Windows (even for AMD64), Red Hat and Suse Linux, there were also FreeBSD drivers available for download.