The appropriate steps once you have the HighPoint drivers installed:
When completed, you'll be using the HighPoint hardware RAID not Apple's software RAID. And it sounds like that's what you did. The speeds are bit slower than I would expect; did you put an encrypted APFS filesystem on the volume? Or a standard, unencrypted one?
- Configure the RAID volume in the HighPoint web-based utility. Once this is done, MacOS will no longer see the four drives, it will only see one: the 8TB volume.
- Open Disk Utility to put a filesystem on the new volume. This doesn't do any sort of RAID work with the device, it just puts a filesystem on the volume you created with the HighPoint controller.
- Use it.
Thanks very much for the help. Yes i have done all these things so it looks like i set it up correctly. I used APFS. However i have a few more questions. What sector and block size should be used in the highpoint software? I left mine at the default 512B. Also, i tested the speed in blackmagic speed test with the default 5GB stress test.