I have tried the Seagate Barracuda 3TB and imo its just way too noisy for me. So I have decided to pay a bit extra for the WD hdds. So which one shall I get? They are both similar priced yet the Red comes with 3 year warranty. I just want to know which one will be most quiet?

Thank you.

Both my 2TB Greens and 3TB Reds are quiet. Anyway, in your case i would buy WD Red for few simple reasons - no 8s sleep thingy causing hundreds of thousands load/unload cycles in few months and lower power consumption.

Ok thank you bearing in mind this is purely for HTPC use and not NAS. Would it still be a viable option?

My eight 3TB Reds are quieter than the four 4TB Greens that they've replaced, especially under load. I cannot hear them seeking in the case that's right next to my chair.

If you're willing to pay the premium, Red's all the way.

Take that with a pinch of salt, the cycle scare reached FUD levels of paranoia. In my case as a desktop storage drive I use every day, the count is 88,817 - in 735,9 days of Power On Time, which comes to a little over 2 years non-stop. Hardly drive-breaking.

The new WD Reds are review-proven to be quieter, though, so from a silence perspective you should definitely get one of those. You get an extra year of warranty to boot.

Well, i started with 6 WD20EARS. I am down to 2. They got replaced over time by WD20EARX from RMA. I also replaced one WD20EARX due RMA.

My Greens and reds (cycles/hours) :
WD20EARX (Green) - 71834/12074, 6572/4298, 34867/7215, 56511/12034, 67043/12136, 52303/8591
WD20EARS (Green) - 73492/14028, 156826/19464
WD30EFRX (Red) - 12/3032, 12/3032, 1/603, 1/603 (yes, 12 and 1 load cycles for each pair of 3TB Reds)

And these drives weren't even accessed frequently, usually only for 2-3 hours per day (and of course not all of them), so those load/unload cycles are rather high. If i would have these drives in RAID or as a primary data drive, then i would have much, much higher load counts on those Greens.

I find my 2TB WD Red to be very noisy.
As soon as I unplug it and leave it off running with just ssd it's dead quite pc.

I recently bought a 2TB Red to put in one of my old Antec MX-1 enclosures and have found immeasurably quieter seekwise than either of the two versions of Greens I've bought in the last 18 months. Pot luck?

I think it depends on what we consider quite.
I sleep 4m away from my 'server' and during the nights it's very audible, even though most of time it's idling and hdd is not seeking.
But as soon as I leave my serverr unning on SSD only, you can hardly tell there is a pc in the room.

Does the server case have vibration damping mounts for the SSD or is it just hard mounted? It might be more of a case problem than an HDD problem...

I recently bought 2 WD30EFRX for my NAS and they're both louder than a WD20EARS I also have.

Why not just disable the load cycling? There are several tools for different operating systems which can set load cycling interval, or disable it entirely. My three years old WD10EARS have done 74 and 77 cycles, respectively. My latest drive, less than a year old, has done eight.

Edit: These drives are on 24/7 and see both lots of active use and lots of idle time.