A couple of months ago we reviewed JMicron's JMF667H reference design SSDs, which did relatively well in our tests especially when taking JMicron's previous SSD controllers into account. As always, reference designs are only meant for evaluation and do not make their way into retail, so today we are taking a look at Transcend's SSD340.

The SSD340 is based on the same JMF667H controller, although the firmware is an older version than what we tested in the reference design SSDs. Transcend told us that they currently have no plans to update the firmware to the newer version, which I am guessing is due to using customized firmware. It is actually quite rare that OEMs use the stock firmware as typically the OEMs request some changes and customizations, making it slower and more difficult to upgrade the firmware. I would not even be surprised if some OEMs did not upgrade the firmware to ensure product differentiation because it is obvious that OEMs do not want their low end drives to jeopardize the sales of higher cost (and profit) drives. 

Update 8/18: Apparently Transcend has released a new firmware for the SSD340. I will try to find some time to test the new firmware and will provide an update if anything changes. 

Transcend SSD340 Specifications
Capacity 32GB 64GB 128GB 256GB
Controller JMicron JMF667H
NAND Micron 128Gbit 20nm MLC
Sequential Read 189MB/s 364MB/s 530MB/s 518MB/s
Sequential Write 37MB/s 73MB/s 145MB/s 285MB/s
4KB Random Read 19K IOPS 33K IOPS 62K IOPS 67K IOPS
4KB Random Write 9K IOPS 17K IOPS 35K IOPS 68K IOPS
Idle Power 0.53W 0.53W 0.54W 0.55W
Load Power (Read/Write) 1.08W / 1.14W 1.41W / 1.33W 1.52W / 1.98W 1.63W / 3.75W
Endurance 33TB 66TB 106TB 141TB
Encryption No
Warranty Three years

The SSD340 is available in capacities ranging from 32GB to 256GB. The JMF667H actually has a capacity limit of 256GB, which also limits the SSD340 to just 256GB. We should see JMF670H make its entry later this year with support for 512GB, but until then 256GB is the highest you can go with a JMicron controller.

Like nearly all client SSDs, the SSD340 has a three-year warranty with an endurance limitation. Quite surprisingly the endurance scales with capacity, although the scaling is not exactly linear. Nowadays most client SSDs only have a single rating for all capacities, so it is pleasant to see a scalable endurance for a change. I am pretty sure many OEMs just artificially lower the spec to make sure that enterprises customers do not choose the lower profit consumer drives, as the difference between high-end client and entry-level enterprise drives is quite indeterminate (i.e. entry-level enterprise drives are usually based on client platforms).

Transcend's data sheet for the SSD340 states that the drive supports DevSleep, although there are not any actual power figures listed aside from normal idle, which are way too high for DevSleep. Since the controller supports DevSleep, I have to wonder why Transcend has not published any power figures; we'll check power later on to verify whether the SSD340 actually supports DevSleep.

Transcend uses Micron's 128Gbit 20nm NAND in the SSD340. Our 256GB review sample had a total of sixteen NAND packages (eight on each side of the PCB), meaning that each package is a single-die package with one 128Gbit (16GB) die. There is also Samsung's 256MB DDR3-1600 DRAM chip working as a cache. 

Test System

CPU Intel Core i5-2500K running at 3.3GHz (Turbo and EIST enabled)
Motherboard AsRock Z68 Pro3
Chipset Intel Z68
Chipset Drivers Intel + Intel RST 10.2
Memory G.Skill RipjawsX DDR3-1600 4 x 8GB (9-9-9-24)
Video Card Palit GeForce GTX 770 JetStream 2GB GDDR5 (1150MHz core clock; 3505MHz GDDR5 effective)
Video Drivers NVIDIA GeForce 332.21 WHQL
Desktop Resolution 1920 x 1080
OS Windows 7 x64

Thanks to G.Skill for the RipjawsX 32GB DDR3 DRAM kit

Performance Consistency & TRIM Validation
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  • KAlmquist - Tuesday, August 5, 2014 - link

    Back in the days of the JMF602 controller, I thought about buying one to store program files on (meaning I would be doing pretty much nothing but reads on the device and the write problem wouldn't matter). But the prices on the JMF602 drives never dropped to the point where this made sense. I eventually bought an Indilinx drive for about the same price as a J-Micron drive.

    It seems like history is repeating itself.
  • Per Hansson - Wednesday, August 6, 2014 - link

    You should be very glad you did not.
    I bought a 32GB JMF602B based Transcend TS32GSSD25S-M SSD in April 2008.
    This was before even the first Intel X25-M 50nm SSD was released so there was not much on the market to choose from if you wanted a "cheap" SSD
    Mind you cheap in this case was actually 1495SEK which translates to over $200!

    Performance is appalling, this is the type of SSD which you could not install Windows Vista or 7 on, because you would get "delayed write failed" errors during the installation, the SSD was simply so slow that the installation program timed out when copying the files...

    I'm using it for a Linux based firewall, IPCOP which is a 40MB ISO install, it took over 30 minutes to install!
    With a 2GB SCSI disk the same install is over in under 5 minutes, just for reference!

    Initially I gave this SSD a 2/10 score, because for my use it worked fine and I had not had any problems with it.
    But now just last week when rebooting the machine the vmlinuz boot file in /boot was corrupted.
    I can only conclude that the SSD has not refreshed the data in flash and that some bit flips has occurred, I made a HEX comparison of the file with a known good one and there where 4 errors in the file.
    Restoring the file from the original ISO made the system able to boot again, but it just goes to show what amazing crap this company makes!
    I sure would not take the bet that they have learnt anything in the last 5 years, especially so when they are probably using the crappiest flash they can find to get the price down, which they obviously have failed at when the MX100 is cheaper & performs miles better!
  • KAlmquist - Wednesday, August 6, 2014 - link

    That drive sounds bad. Even if one were to excuse Transcend for not refreshing the flash, the drive still should have detected the data corruption.
  • TonyCL6 - Thursday, August 7, 2014 - link

    For a SSD controller to be able to make crappiest flash a working SSD requires strong R&D capability in both hardware and firmware. That is the Midas touch solution/ technology that flash memory vendors and module makers are eager to have.
  • henrykale - Wednesday, August 6, 2014 - link

    It's an easy call to start promoting video testimonials with Modulates, then you can publish them to Facebook or your website or Twitter.
  • GraphicDesign - Thursday, August 7, 2014 - link

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  • cklee16 - Friday, September 26, 2014 - link

    Any idea if the updated firmware improved the performance of this drive?


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