drives

Hello Ip Cam Talk, I'm currently running 1 'rebranded' Hikvision ds-2cd2332-i, using Blue Iris on my desktop PC. I'm wanting to expand, probably 4 cams total near term, up to 8 cameras max, since the gigabit POE switches I'm looking at have 8 ports. Leaning toward the Thinkserver ts140 with...

What hard drive does everyone recommend? I am entertaining the Western Digital Blue or Green drives. I am unsure how the NVR works, does it keep the drives spinning constantly, or does it only spin up the drives when it senses motion and records? Obviously if I was recording 24/7 I would go with...