Question 1

4 of these drives good for 32tb 24/7 dlna nas server? Don’t want to beat a dead horse here... Really it’s just to stream my 10Bit 4K movies using DLNA

Accepted Answer

It all depends on what size and what RAID configuration you are asking about.  Most people would be using RAID 5 or something like Synology's SHR (similar to RAID 5 but doesn't require equal size hard drives) for this purpose. If you are thinking that 4x8TB will give you 32TB of storage that is not correct in RAID 5 because of the overhead used for data protection.  It works like this for RAID 5, 4x8TB = 24TB storage, 4x10TB = 30TB storage, 4x12 = 36TB storage.  So first determine which RAID configuration works best for you and then find a RAID calculator available online to choose your RAID configuration and hard drive size.  If you just want speed, with no parity checking then you could go with 4x8TB or 2x16 TB (whichever is cheaper) in RAID 0 for 32TB of storage but file corruption could be an issue and there is a possibility that you can only do 2 hard drives in RAID depending on your hardware.
Having said all that, these drives will certainly stream 4k 10-bit HDR movies over DLNA.  Streaming 4k is just as much up to the software and hardware of your computer than it is the hard drives.  A nicely configured Windows machine, for example, may stream them fine however a less powerful NAS device may not.  There are a lot of moving parts but these drives will not be an issue.  There are also issues with playing the 265 codecs in Windows 10 Media Player but the same files that will not play in Media Player, will stream via DLNA to my LG TV just fine and play in full 2160p HDR with no problem.  These same files will show up fine in my 9 year old NAS but will not stream via DLNA on it but photos stream fine.  So it all depends on your exact configuration.  But the drives are fine.
If it all gets too hard then just get a fast (say 400 MB per second) USB stick and copy 10 movies at a time on to it and plug it into your TV.  The Samsung BAR Plus 256 GB works well for this in my experience.  You can also look into getting streaming server software on your computer and a client connected to your TV.

Question 2

What is the difference between this and the WD Black drive?

Accepted Answer

The Red is engineered for 24/7 usage.  The Black is not.

Question 3

Is the red wd drives better for cctv/nvr in raid setup than the purple drives? i hear purple drives are not lasting long. both red and purple are 24/7

Accepted Answer

I use my purple drives with 9 cameras 24 x 7 and have over three years without a single failure.  pretty good if you ask me.

Question 4

Can I use this as an external storage for my desktop?

Accepted Answer

I have four of the earlier 3tB versions of this drive in external USB3 enclosures and use them in rotation for critical full system backups. They have served very well in that capacity. I also have one of the 3tB drives in my main daily-driver computer now and it does that quite well although it isn't as fast as some but since it is used mostly for secondary data store it doesn't matter so much. The reason that I have so many of the older 3tB drives is that I upgraded all of the drives in my Drobo NAS to 6tB drives a while back. Those drives as well as five of the 8tB units in another NAS have worked perfectly so I can highly recommend them (for the proper use, of course).

ASIN	B08K3VVKSW
Best Sellers Rank	8,875 in Computers & Accessories ( See Top 100 in Computers & Accessories ) 22 in Internal Hard Drives
Box Contents	Contents: 1 item
Brand Name	Western Digital
Cache Memory Installed Size	512
Color	Black
Compatible Devices	Desktop, Laptop
Customer Package Type	Retail/Shipping Packaging Protected
Customer Reviews	4.0 4.0 out of 5 stars (1,786)
Data Transfer Rate	6 Gigabits Per Second
Digital Storage Capacity	16 TB
Enclosure Material	Aluminium
Form Factor	3.5-inch
Global Trade Identification Number	00718037877662
Hard Disk Description	Mechanical Hard Disk
Hard Disk Form Factor	3.5 Inches
Hard Disk Interface	Serial ATA
Hard Disk Rotational Speed	7200 RPM
Hard-Drive Size	16 TB
Hardware Connectivity	SATA 1.5 Gb/s
Hardware Platform	PC
Installation Type	Internal Hard Drive
Item Type Name	Western Digital WD Red™ Pro 16TB Internal Hard Drive 8.9 cm (3.5 Inch) SATA 6 Gb/s WD161KFGX Bulk
Item Weight	690 Grams
Manufacturer	Western Digital
Manufacturer Part Number	WD161KFGX
Media Speed	200-250 MB/s
Model Name	WD161KFGX
Model Number	WD161KFGX-SPAFPN0
Network Connectivity Technology	SATA
Number of Items	1
Product Features	Portable
Product Warranty	1 year
Read Speed	259 Megabytes Per Second
Specific Uses For Product	Business, Multimedia, Personal
UPC	718037877662
Unit Count	1.0 count

WD Red Pro 16TB NAS 3.5" Internal Hard Drive - 7200 RPM Class, SATA 6 Gb/s, CMR Recording Technology, 512MB Cache

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