KingDian S280 480GB SSD, just a fast SSD

A few months ago, I finally “moved” to a new computer, and while getting used to it, I ran into a problem related to my work.
The inspection, tests, and explanation are, as always, below the fold.

The tricky part of moving was that I usually need to keep certain working files on my computer. When I set the old computer aside, I immediately installed a regular 500 GB hard drive in the new one (you may have seen it in my reviews).
I worked like that for about a month. Everything was great, except for the noise—I wanted a completely silent computer, after all. To be honest, I didn't expect a 2.5-inch drive to be so noisy—or, more precisely, to hum so loudly. It also got noticeably hot because of the computer case's design.
So I moved everything to network storage, but it wasn't very convenient to use because the speed was only 100 Mbps. I replaced the router in the process and got Gigabit Ethernet, but it was still uncomfortable: opening 5–10 files of 2–3 MB each at once was enough to make me miserable.

In other words, I tried to solve the problem in various ways, but the hard drive inside the computer got hot and hummed, while network storage was slow—or, more precisely, had high latency. So I decided to install an SSD. Since my files took up about 240 GB, I figured I needed a 480 GB SSD.
Since I wasn't particularly concerned about data security (I make an automatic daily backup of everything), and raw performance wasn't important either, I decided to get a Chinese SSD.
It cost me $115, thanks to the points I'd accumulated.

The SSD comes in a thin cardboard box that didn't even get dented in transit. That was a little surprising, since just a few days earlier I'd received some drill bits, and their box had been crushed to about half its original size.



I could barely find any information on the back confirming that this was actually the S280 480GB.



It looks like an ordinary thin, lightweight metal box.



Before testing, I also took a look inside :) The case isn't even screwed together. There are small holes in one half and tabs on the other, forming simple snap-fit clips. There weren't even any warranty stickers. There were a few small scratches after I opened it, though—maybe that's how the manufacturer can tell the device has been opened.
On the other hand, mSATA and M.2 drives are just circuit boards anyway.



The circuit board takes up about half the case. One side has an empty spot for memory chips; I'll take a guess that it's for the 1 TB version.





It uses the fairly well-known SM2246EN controller (interestingly, here they wrote about the SM2256). The memory consists of two 256 GB TLC chips. Besides the controller and memory chips, the top side also has power converters.
The back of the board has a RAM chip for the 512 MB cache (the 120 GB and 240 GB versions have 256 MB), as well as another voltage regulator.



Since I didn't want to open up the computer just yet, I did the first round of tests using an external USB enclosure. I also wanted to see what it could do.



Next, I create a partition and format it. I found it more convenient to use the whole drive as a single partition, even though my 250 GB Samsung system drive is split into two.



After formatting, 447 GB is available to the user. If we count in multiples of 1000 rather than 1024, then 480,000,000,000/1024/1024/1024 = 447.03, so everything checks out.



Interestingly, the SSD already had 1 hour of use, 6 power-ons, and at least 626 GB written.



For comparison, here's my Samsung SSD, which has been running 24/7 since last fall.



First, I ran a utility to test the drive's actual capacity—not to test the capacity, but to see how hot it would get.
Yes, I remember the discussion in the comments not long ago about an SSD heating up in a plastic enclosure, so out of curiosity I decided to test it by first writing to the entire drive and then reading it all back.
By the way, the speed shown in the screenshot stayed at the same value throughout the test.



It got a little hotter while writing than while reading. Writing the entire drive (and reading it, for that matter) took about 35 minutes.



For installation in the computer, I cobbled together this setup.
There used to be a hard drive in there, but as I mentioned, it got very hot and was noisy, so I simply removed it altogether. I even had some photos of the drive and the installation process, as well as measurements of the heat spreader plate under the processor, but apparently I accidentally deleted them :(
Anyway, I used a SATA cable from another computer (this one needs a fairly rare cable), and split the power using a SATA power splitter.



Now for some more realistic tests. The drive was empty during testing.
First up is the familiar CrystalDiskMark, 5 passes, 32 GB.



Anvils



AS SSD



Next, I copied all the files I needed from the network storage onto this SSD. That immediately filled more than half the drive (about 250 GB), and I started filling the remaining space with movies just to test it.
The sequential transfer speed over the network is about 100 MB/s, but in practice, that doesn't help much when working with small files.



After writing like this several times, the drive warmed up to about 56 degrees, then the temperature quickly dropped to 52 degrees..



I deleted the files I had copied for the test, leaving 250 GB occupied, and continued testing with other software.



HD Tune





And of course, there's the fairly well-known SSD-Z utility.
Strangely, it reported that the drive has an SM2256K controller, even though the photo clearly shows an SM2246EN. So which should I trust here: the software readout or my own eyes?
This test was run after all the other experiments. During use, the temperature fluctuates between 47 and 50 degrees; that's because the computer has passive cooling and it gets pretty hot inside. The Samsung runs a little cooler, at 45–47; it's mounted near the rear panel.



Some time later, I decided to run a few more tests.
Since I tested the speed with h2testw at the very beginning, I repeated the test with the drive installed in the computer.
The results are better than with the USB enclosure, but not as good as in the other programs.


I was already getting disappointed, since I knew that writing starts out in "fast" mode, but eventually switches to "slow" mode, where TLC memory operates.
I started a test writing a single file larger than 50 GB. The write speed stayed at the same level the whole time, a little over 400 MB/s.
The data was read from a Samsung 850EVO SSD.


Then I decided to run the test in the opposite direction. Since the KingDian reads quite quickly, I tried writing to the Samsung 850EVO.
And that's where the effect mentioned above showed up: write speed starts at 500 MB/s, but then quickly (after just 5–7 GB) drops to a modest 220 MB/s (averaging it out, it's only 180–200). So the KingDian writes twice as fast as the Samsung.


After this operation, the SSD heated up to 63 degrees; before that, it was at 51 degrees.


For now, I'll keep an eye on the SSD and monitor how it performs. It's been running for at least a few days, and I've rewritten its full capacity several times. I tested the second half more extensively, so that's the part I'll keep checking periodically.
My Samsung has accumulated less written data in four months than the drive under review has in just a few days, so I consider this test quite adequate. By the way, the KingDian doesn't report its power-on time accurately: it shows just 8 hours, even though the actual figure is much higher. The Samsung is much more honest about this.

Pros
Good read/write speed
Solid construction
Cache memory
Runs cool

Cons
Unclear situation with the controller type
Price
Uncertainty about the warranty.
The flash memory's origin is somewhat questionable.

My verdict: this is a perfectly decent SSD. I can report back on how it holds up in one of my next reviews. The mismatch in the controller type surprised me: one type is listed, but another is actually installed. But I was quite pleased with the read/write speed, even though, to be honest, the more modest specs would have been enough for me.
After buying it, I was disappointed to spot a Kingston SSDNow UV400 at the same price in a local store. The only consolation was that I bought mine with points, so it worked out cheaper, and the KingDian has 512 MB of cache versus 256 MB on the Kingston. But Kingston has a warranty and a reputation.
There's also a more detailed test of the KingDian SSD that may be useful.

It later turned out that the drive actually has MLC flash memory, not TLC, which explains its high write speed.