First post ever. Just want to share how I solved the noise
problem of the Lorex NVR I bought from Costco.
The unit is not as loud as some of the 1U servers I've dealt
with, but it's definitely too loud for a home environment.
Most of the noise comes from the 40mm fan in the power
supply unit. The fan is soldered to the board within PSU so
it can not be swapped easily for a quieter fan. The
PSU has a standard FlexATX form factor, but in addition to
12V output it also has 52V output for the onboard POE switch.
I can't easily find a PSU with 52V output.
At that point I was ready to return the unit. But thanks for
the instructions in this forum on how to set up cameras on
a separate POE, I put all 4 cameras on a separate fanless
POE switch that I already have and verified everything works
fine.
Without the need for 52V output, it's much easier to replace
the loud PSU. The main board and hard drive are powered
by a 6-pin PCIe connector. I could replace the PSU with a
quiet FlexATX PSU, but a cheaper solution is to get a molex
power adapter and a molex to PCIe 6-pin connector. I bought
them from amazon (search for "molex power adapter",
"6 pin pcie" and also "molex y splitter") for about $20 total.
Then I replaced onboard PSU with the molex power brick.
Powered on, everything's good and much quieter, but
the case fan is still making a bit of noise.
I let it run for a while, played with the system while watching
its power draw with kill-a-watt. The whole thing never went
beyond 14W, and the case is just barely warm to the touch.
At that point, I'm pretty confident it doesn't need the
case fan, so I just disconnected the fan from the main board.
Voila! A totally quiet NVR! It's been a week and no problem
whatsover.
TL;DR: I killed Lorex NVR noise by putting cameras on a
separate fanless POE switch and replaced PSU with an
external molex power adapter
