Horribly slow write speed of HDD

Question

I bought a brand new HDD(Seagate ST2000DMZ08, 2TB, 7200rpm) for my desktop PC running Windows 10, a month ago. When I installed it, I was getting about a 230mb/s read speed along with a 195mb/s write speed(tested with Crystaldisk mark). I have a not even 1 year old PC, with 1 SSD, and 2 HDD (one HDD that came already installed and one that I added 1 month ago).

Now I noticed since maybe a week or two that the speed of the second HDD(the one I installed a month ago brand new) is now horribly slow; but only mainly in write speed.

When testing, I get ok read speed(sometimes slower than expected though), but the write speed is just incredibly slow(about 1-3mb/s).

In the windows process explorer, under performance, it says that the average response time for that hard drive is 3000ms+, which isn't normal..

I have no idea why it randomly started to be so slow. And it's only that brand new drive that is so slow. And it was fine in the beginning when I installed it. I used a available SATA power cable that was already in the PC, and I bought a SATA DATA cable (brand new again) since there was no DATA cable provided in the PC.

Could the DATA cable suddenly turned defective? Or the hard drive be?

Solution

I believe that the only explanation is that the disk is defective.

I suggest to activate the guarantee and demand its replacement.

My own experience with Seagate is that they readily replace the disk without asking questions. However, as you will need to send them the disk to get it replaced, prepare and keep some proof before the disk is sent, in case it is actually demanded later on.

I suggest to check the SMART data of the disk, which may contain some hint of the nature of the defect. You may post it here if you want our opinion.

Comments

[Jason]

You didn't say what OS, but depending on that, you may have to manually defragment it. You didn't say what model of hard drive, but you should run the diagnostics from the manufacturer of the drive first.

[William Weifenbach]

@Jason its a Seagate ST2000DMZ08, 2TB and 7200rpm. I am using Windows 10. I will add these details in the post. There is barely 250GB used out of 2TB on the hard drive.

[harrymc]

If you power down the computer and do cold boot, does the speed improve?

[William Weifenbach]

@harrymc No, its still really slow

[William Weifenbach]

Even a brand new 1 month old HDD could be suddenly defective? Because it was fine when I got it, write speed were decent.. Could it possibly be the SATA data or power cable thats defective or?

[harrymc]

Anything is possible, but keep an eye on the guarantee date limit while you are checking. My own opinion is that any such problem should have shown up soon enough, not one month later.

[William Weifenbach]

You are right. I think im going the check the cable just in case, since the data cable I bought was pretty cheap.. maybe the quality was pretty bad too. And the drive is definately still under warranty, I think Seagate warranty for HDD is 2 years. I just hope the issue is not coming from the PC itself(motherboard or other) but I doubt it.

[harrymc]

I agree that if the cable was installed by yourself then it should be checked, just in case, before claiming guarantee. Cable quality does matter.

[William Weifenbach]

well the PC already had a not in use SATA power cable tied next to the original hard drive in the case. So I took the Seagate hard drive I had bought a month ago, screwed it in the right spot, then connected that one sata power cable to it, and then i bought a SATA DATA cable in an electronics store for a little less than 5$ and connected the seagate HDD to the motherboard using that sata data cable. And it was working perfectly in the beginning. I also have an external 3.5" HDD USB enclosure, I could test the HDD using it to see if the HDD is really the problem or not.

[harrymc]

Yes this would be a clincher. Document all results, just in case.

[William Weifenbach]

Also, the S.M.A.R.T. status of the Seagate HDD says its Good(I used Crystaldisk info software) and that theres no problem; can a HDD be defective like this without the S.M.A.R.T. status showing any problems?

[harrymc]

You can also use SeaTools to analyze problems and perhaps install firmware. It didn't particularly help me in my case, but may help you.

[William Weifenbach]

I just tested Seatools and im getting the same results, all test are passing without problems, including the SMART test

[harrymc]

Question: Does your test do sequential or non-sequential writes? These low-capacity drives have horrible non-sequential write speed.

[William Weifenbach]

When using Crystaldisk mark, I awlays do the Sequential(SEQ) test. And still I get barely 1mb/s write speed using a 50mb test file, however I get a read speed of about 300mb/s during that same test with the 50mb file

[harrymc]

The technology of these disks makes for very slow writes and fast reads. But your speed is still exceptional. I don't really believe that a bad cable would cause only slow-downs and no errors. What I really think and didn't dare say: I would return the disk for reimbursement and buy a better disk, if possible, (but these are costlier).

[William Weifenbach]

by "better disk" , do you mean SSD? Because since this disk is only for storage, I dont really need SSD performance. Or maybe you mean a different brand? I am aware that Seagate had often bad reviews in the past compared to WD, but I have another seagate disk(2.5") that I had since november 2018 and is still so far so good, so when I went for seagate again for this 3.5" one.. but maybe it was a bad idea

[harrymc]

SSD is lousy as long-term storage, to be avoided. You have a slow-writing disk, but if this disk is write-once-and-forget then it's OK. But something is wrong with this one.

[William Weifenbach]

I tried to test it using my USB enclosure, but looks like the enclosure is defective as well, the PC detected the HDD for maybe 30 seconds, and then I heard the Windows noise meaning the device was disconnected while it was still connected. Im going to get a new enclosure, test to make sure its really the HDD that is defective, and then make warranty claim if it is. I use this maybe defective HDD for storage but also I put PC games on it- that being said games run just fine even from that HDD, but when a game has a patch, it takes forever to install since it writing operations on the HDD

[William Weifenbach]

So I bought another SATA to USB enclosure, its a USB 2.0 one but I could still get an idea-- and it turns out that when I use the USB enclose and connect it to a different PC, im getting much higher read and write speed(about 35-40mb/s in both read and write speed, wich makes sense for USB 2.0 interface). So im guessing the drive isnt defective, the problem comes either from the SATA cable, or the motherboard itself--is it possible that its not getting enough power from the SATA power cable from the PC?(wich would be weird because it was in the beginning then). Imgoing to try changing DATA one

[harrymc]

This might be after all your SATA cable, which would be the easiest to fix. Cables actually can go bad if they are low-quality.

[William Weifenbach]

I just ordered a new one(data cable). I doubt the power cable that was already there in the PC case is faulty.Hopefully the data cable is gonna be the cause of problem, and not the motherboard/sata port.

[William Weifenbach]

So I just replaced the SATA cable, and now im getting more decent speeds. So the sata cable was actually the problem. However, when doing the same sequential speed test, im getting about 205mb/s read speed, and about 90-105 mb/s write speed, wich is far from the 192mb/s write speed I was getting in the beginning with the previous cable before it got defective.. Maybe the fact that the HDD was brand new with no data on it helped on getting speed such as 192 mb/s write speed? because now im only getting 100mb/s write speed(theres about 250GB of data on the HDD now)..

[William Weifenbach]

Edit: So I thought it was fine, until after 20minutes, now im back at getting super slow write speed and decent read speed... I really dont understand whats going on..

[harrymc]

Perhaps the disk is defective after all. By the way, I don't like at all the specs of this cheap model.

[William Weifenbach]

Im gonna try one last time to replace the data cable again-just in case I would have been really unlucky.. if this still doesnt work, im gonna have to do a warranty claim. Could my PC motherboard be the problem? And not the disk itself. Also may I ask why you dont the specs of it? I thought it was decent since its 7200rpm and 220mb/s sustained speed, even tho im not getting near that speed at all at the moment

[harrymc]

This model was designed to have very slow writes but good read speed. If your aim is to have fast writes, then this model (and this technology) is not for you.

[William Weifenbach]

well very slow speed, but to the point of 1-5 mb/s write speed? I think theres something wrong somewhere... I would expect at least 40 or 50mb/s even from a slow drive. Could the motherboad be the issue? Or is this pretty unlikely? Thank you

[harrymc]

I guess that the disk is faulty. The very slow speeds I have seen mentioned for this model were around 80mb/s. People doing backups mentioned letting it run overnight because it took so long.

[William Weifenbach]

Yeah, well like I said im gonna test with 2 other brand new sata cable see if it works. If not, disk is faulty I guess. However remember a while ago I had tested the drive with a sata to usb 2.0 enclosure, and I was getting about 40mb/s write speed wich seems pretty normal for USB 2.0. So im really confused on if the disk is really faulty or not, or if its the sata cable, or something else..

[William Weifenbach]

UPDATE: I requested a warranty claim and they sent me a brand new HDD of the same exact model. Tested it and right now im getting what the previous one was getting when it was brand new too, wich is about 220mb/s read and 215 mb/s write.. will see if it keeps that speed in the long run..