Expanding storage capacity for cams footage - request input

Virga

Pulling my weight
Feb 13, 2023
212
151
USA
I would like to expand storage capacity for cams footage.
Request suggestions on what might be good ways to do this.

In 2023 January I had started with Blue Iris on PC hardware I had at hand at the time. In 2023 December I bought three 4TB WD purple drives and they were not too expensive at that time.
I have a small form factor (SFF) PC dedicated to Blue Iris, and its ITX mobo has four SATA ports.
500 GB M2 SSD - Windows and BI
250 GB SATA drive - misc. drive for stuff I export, and BI housekeeping
Three SATA 4TB WD purple drives - contain the output from cams
The existing SFF case can only take three 3.5 inch drives plus two 2.5” drives.

My first thought would be for a new mobo with many SATA ports.
The market for enthusiast PC builders seems to have dried up over the last couple of years.
There are very few mobos available these days, and they do not seem to come with more than four SATA ports, perhaps because the action has moved to M2 drives and therefore ports.
If I were to start with a new four SATA port mobo, then I may as well as expand my existing mobo, and avail of the existing CPU, memory and Windows license.

Existing:
mobo Z690M-ITX/ax LGA 1700
CPU Intel Core i5-12600K (Passmark 27,758)
memory 16GB (2 x 8GB) DDR4 3000 (PC4 24000)
video card GTX 960 - one PCI slot only on mobo, this was a card at hand from years ago, don’t know if it is really helping BI
In 2024 February this mobo and CPU were a $227 upgrade from original BI starting PC, and gave me two Ethernet ports, a Windows 11 compliant PC, and Passmark score went from 5,636 to 27,758.

While the ITX mobo is currently in a SFF case, I have cases and power supplies from older builds that I could move everything to and have room for eight SATA drives.
For $50 I could get an expansion card that would go in the solitary PCI slot on the mobo, and provide SATA slots 5, 6, 7, & 8. This would mean giving up on having a video card in the BI PC.
Then I wait for a buying opportunity on more WD purple drives and meanwhile deploy additional drives from at-hand WD Gold enterprise grade 2TB and 1TB drives from years ago.

Thoughts?

*** I did read this recent thread on utilizing existing hard drives: