Question Trying to compare hdds

tinpanalley

Golden Member
Jul 13, 2011
1,451
22
81
I'm looking at two really great deals, and one is for a straight up 4TB Seagate Barracuda. But the other is for something I've never owned, an external 8TB WD Elements. My question is how will the external compare to the internal in terms of transfer speeds? This will only be used to backup media, not likely to be used for actually accessing for playback. So, several gigabytes at a time of transfers. Just wondering if I'm not better off going for something that connects SATA internally.
Any thoughts?
 

mv2devnull

Golden Member
Apr 13, 2010
1,498
144
106
Such external drives have two "levels":
* One is the interface. That WD model has USB 3.0 that can in theory transfer 625 MB/s. SATA 3 has 600 MB/s, theoretical. Formally no real difference. HDD's are not that fast, so the interface is hardly the limiting factor.
* The other is the actual disk inside. It is some SATA drive, but the vendors like to hide the exact model (so they can change it without notice). Basically you would have to buy and open before you know what you are actually comparing.

External is a bit easier to move to another machine. External does not have to be connected all the time (but takes some space).
 

tinpanalley

Golden Member
Jul 13, 2011
1,451
22
81
External is a bit easier to move to another machine. External does not have to be connected all the time (but takes some space).
Yeah, obviously the external has other logistical benefits but with only one machine that isn't of any benefit here. Apparently the WD Elements at 8TB is a white label PMR drive, most likely a WD80EMAZ.

What I don't quite understand is the Molex to SATA adapter people are recommending for getting it to work internally. I don't like the electrical tape idea because that can come loose and cause all kinds of heating and electrical problems. Just unsafe in my opinion, but I don't understand the adapter solution. Any help there?
 

kschendel

Senior member
Aug 1, 2018
264
193
116
What I don't quite understand is the Molex to SATA adapter people are recommending for getting it to work internally.

There's probably an assumption that you have no free SATA power plugs left on your existing SATA power cable. If you still have ordinary SATA power available from your PSU, just use that, no need for an adapter.
 

VirtualLarry

No Lifer
Aug 25, 2001
56,340
10,044
126
There's probably an assumption that you have no free SATA power plugs left on your existing SATA power cable. If you still have ordinary SATA power available from your PSU, just use that, no need for an adapter.
No, it's because current-spec SATA HDDs power-down when presented with a signal on the SATA power connector's +3.3V line. Molex-to-SATA adapters don't have this line, so they bypass the "problem".
 
  • Like
Reactions: tinpanalley

tinpanalley

Golden Member
Jul 13, 2011
1,451
22
81
No, it's because current-spec SATA HDDs power-down when presented with a signal on the SATA power connector's +3.3V line. Molex-to-SATA adapters don't have this line, so they bypass the "problem".
That's what I had read. The thing is that doing this requires either A) the adapter thing that I've heard can cause electrical issues if the adapter isn't great quality, or B) the electrical tape thing which I'm not crazy about as a solution either.
Ultimately, I need a 7200rpm drive in this case anyway so this kind of drive isn't right for me despite the deal on offer.
 

aigomorla

CPU, Cases&Cooling Mod PC Gaming Mod Elite Member
Super Moderator
Sep 28, 2005
20,846
3,189
126
Friends do not let Friends buy seagate.

Seriously seagate is probably the riskiest drive to buy next to the noname ones which try to copy name brands like WL, trying to confuse the buyer to think its a WD.

Like This..

That is definitely not a Western Digital.

I would recommend HGST >= Western Digital ~ Toshiba.
It would need to be a sad sad day and one where i drank a lot of alcohol to buy a seagate, because me being drunk would be the only excuse for buying a Seagate.
 

mv2devnull

Golden Member
Apr 13, 2010
1,498
144
106
Backblaze has "some" harddrives and has for years published their statistics:
They had HGST, Seagate, and Toshiba (and one WD model) in use during 2020.
Seagate has been least reliable.
 

Fallen Kell

Diamond Member
Oct 9, 1999
6,039
431
126
Yeah, depending on usage, it is hard to recommend either of those drives to be honest. Personally I picked up Toshiba MG07ACA14TE drives for my storage server (these are 14TB). Backblaze first tested with this model of Toshiba before then purchasing over 20,000 drives, but they switched to the MG07ACA14TA model. It is the same drive, just with a firmware tweak so that it presents as a straight 4k block size. The "TE" has a firmware to present as 512 block size to support additional/older controller cards that might not recognize the newer 4k block sizes, and it also has persistent write cache for data loss protection on power failure. So I paid slightly more for the write loss protection on power failure and to make sure it was recognized in my SAS controllers (even though my system is on battery backup, it is possible that it doesn't shutdown cleanly during a power loss event, so I wanted to make sure writes to the drive are properly handled even with a power loss).

I think these are some of the best still on the market if you need a larger amount of storage. HGST is also a decent manufacturer, but I havn't seen as much information on their larger sized disks (i.e. over 8TB) Their smaller 2-4TB drives seem to have been rock solid, but those drive sizes don't run into the same problems that the larger ones do (i.e. you don't need helium filled drives at those sizes because you don't need 7-9 platters in the drive).
 
Last edited:

mikeymikec

Lifer
May 19, 2011
17,708
9,571
136
I shopped for a new internal data drive recently as my 1TB WD Black was getting full a few months ago. I took a chance and got a WD Blue 4TB, going from 7200rpm to 5400rpm (performance is important to me, but I was trying to quieten down my computer too). The Blue routinely manages 160MB-180MB/sec which is what my WD Black (2014) could do. The Blue isn't near-silent though, it just has a different harmonic to the Black. I set it to a 15 minute timeout to quieten the system down.

I was worried about going for another Black because several years ago I encountered a 2TB Black and the noise it made on access drove me mad, I swear drives ~25 years ago were quieter!

One thing though, USB3 is definitely slower than SATA, I think it's because of two things: 1) latency. 2) I suspect that NCQ doesn't work over USB. I didn't keep the ATTO results, but my Blue 4TB started out over USB while I was migrating data, and the results were vastly different for low-size transfers (IIRC ext was like a crappy laptop HDD from ten years ago, internal was about 5x faster).
 

kschendel

Senior member
Aug 1, 2018
264
193
116
...
I was worried about going for another Black because several years ago I encountered a 2TB Black and the noise it made on access drove me mad, I swear drives ~25 years ago were quieter!
...

I've decided that it's sample dependent. Prior to the dev machine I have now, I did most of my serious software development work on a 2009 Mac Pro running linux, with 4 of the OEM 640GB drives. They were fairly unobtrusive, not silent by any means but not annoying. About 9 months in, one drive failed, and I replaced under warranty. The replacement drive had the exact same model number but was audibly different, clickier and more annoying.

Fast forward 8 years and I decided to replace all of the old drives with an SSD and a couple replacement WD Black 1TB's. One of the Blacks was virtually silent, definitely the quietest hard drive I've ever had outside of 2.5" laptop drives. The other ... well, let's just say not so much. I ended up buying a third WD Black (all three were WD1003FZEX's) and it was on par with the original 640GB drives.

So 3 drives, all bought within a year, all with the same model number, ran the gamut from as close to inaudible as a hard drive gets, to normal, to throw that fscker out the fscking window.

I've had similar experiences with UltraSCSI drives although not as extreme.