The Crucial BX200 (480GB & 960GB) SSD Review: Crucial's First TLC NAND SSDby Billy Tallis on November 3, 2015 9:00 AM EST
SSD manufacturers are under constant pressure to reduce prices and increase capacity, but the pace of Moore's Law is never enough to satisfy consumers. As the SSD industry has matured, manufacturers have turned to other strategies for driving down costs, making tradeoffs to better suit what customers want. Early on, we saw a shift from single bit-per-cell SLC NAND to two bit-per-cell MLC, doubling capacity for the same size of chip (and therefore, cutting cost per GB in half). Currently, the industry is transitioning to 3D NAND techniques that allow for more storage capacity on a chip of a given size without requiring circuit elements and memory cells to shrink. Portions of the market are also shifting to use three bit-per-cell TLC NAND to get another capacity boost.
None of these advancements in storage density come for free. 3D NAND requires major changes to the manufacturing process, which is why only one of the four NAND manufacturers is currently shipping products with 3D NAND. Likewise, cramming more bits into the same memory cell has reprecussions. The more closely spaced voltage levels in the flash cells requires more careful control and more complicated error correction. It makes reading and especially writing slower, drives up power consumption and decreases durability. Everyone in the industry has struggled to create TLC-based SSDs that can compete on anything other than cost. Samsung has made the most use of TLC, aided by their lead in 3D NAND, but their TLC drives have had issues that have proven tough to stamp out. Despite the difficulty, most manufacturers now feel that TLC has a place in the market and that the downsides can be mitigated enough to suit consumers.
This brings us to Crucial's latest drive, the BX200. As the successor to the very successful BX100, it is a value-oriented 2.5" SATA drive. The BX200 moves to the newer Silicon Motion SM2256 controller and is Crucial and Micron's first TLC drive, using Micron's 128Gb 16nm TLC NAND. Micron's 16nm TLC was announced in June as intended for consumer applications. With a shift to 3D NAND planned for 2016, their 16nm TLC is something of a stopgap solution to further cut costs while temporarily stuck at the end of the road for planar NAND.
Silicon Motion's SM2246EN controller has been a popular choice for low-cost client drives, and when paired with MLC NAND it offers decent performance and very low power consumption. While it technically supports TLC NAND, only the successor SM2256 controller supports the more advanced LDPC error correction that is widely viewed as necessary to get sufficient reliability from a TLC drive. There are now several TLC drives on the market using the SM2256, competing primarily against each other and earlier SM2246EN drives with MLC, and MLC and TLC drives using Phison S10 controllers. Further up the price and performance scale are mid-range MLC drives and Samsung's TLC-based 850 Evo.
|Crucial 480/500/512GB SSD Comparison|
|Controller||Silicon Motion SM2246EN||Silicon Motion SM2256||Marvell 88SS9189|
|NAND||Micron 16nm 128Gbit MLC||Micron 16nm 128Gbit TLC NAND||Micron 16nm 128Gbit MLC|
|Sequential Read||535 MB/s||540 MB/s||555 MB/s|
|Sequential Write||450 MB/s||490 MB/s||500 MB/s|
|4kB Random Read||90k IOPS||66k IOPS||100k IOPS|
|4kB Random Write||70k IOPS||78k IOPS||87k IOPS|
|Endurance||72 TB||72 TB||160 TB|
The BX200 specifications show only moderate performance increases over the BX100, except for the random read speed which is significantly decreased. The higher program and erase times of TLC NAND are probably the most difficult downside to mitigate, as SSDs have always been trying to compensate for their much higher latency than DRAM. Throughput can be increased by using multiple flash chips in parallel, but random read performance ultimately is limited by how long it takes the drive to fetch any data from the flash chips, so some decrease was probably unavoidable.
With the BX200 Crucial is retiring the 128GB capacity class. As flash memory gets cheaper, the fixed costs of the controller and other components come to dominate the budget and smaller capacity drives end up costing more per GB than mid-range capacities. Additionally, the smallest capacities have the least ability to provide parallelism, which can hobble their performance.
For most of the charts in this review, I've highlighted in blue the other TLC drives we've tested.
|AnandTech 2015 SSD Test System|
|CPU||Intel Core i7-4770K running at 3.5GHz (Turbo & EIST enabled, C-states disabled)|
|Motherboard||ASUS Z97 Deluxe (BIOS 2501)|
|Chipset Drivers||Intel 10.0.24+ Intel RST 220.127.116.110|
|Memory||Corsair Vengeance DDR3-1866 2x8GB (9-10-9-27 2T)|
|Graphics||Intel HD Graphics 4600|
|Desktop Resolution||1920 x 1200|
|OS||Windows 8.1 x64|
- Thanks to Intel for the Core i7-4770K CPU
- Thanks to ASUS for the Z97 Deluxe motherboard
- Thanks to Corsair for the Vengeance 16GB DDR3-1866 DRAM kit, RM750 power supply, Carbide 200R case, and Hydro H60 CPU cooler
Post Your CommentPlease log in or sign up to comment.
View All Comments
Shadow7037932 - Tuesday, November 3, 2015 - linkThat's kind of disappointing, esp. the 250GB version as it's only a little cheaper than the 850 EVO. However, the 960GB assuming sales/deals, go down to $230-250 in the coming months, I can see people buying it to replace HDDs for say storing games.
eek2121 - Tuesday, November 3, 2015 - linkThat's MSRP for the BX200. The street prices will probably be much cheaper.
Samus - Tuesday, November 3, 2015 - linkFor the price your still better off with the OCZ ARC100 with toshiba MLC and. Barefoot3 controller.
LB-ID - Tuesday, November 3, 2015 - linkToshiba's still selling things under the OCZ name? It long since needed to die and go away.
Lazlo Panaflex - Friday, November 6, 2015 - link+1 to that. Lots of people got burned by bad OCZ drives. Pretty dumb of Toshiba to keep calling them that.
tamalero - Thursday, November 12, 2015 - linkReminds me of Hitachi when they bough the IBM dextar drives.
anyone remembers the horrible failures of the 10k and 15k rpm drives under IBM?
even their consumer disks were dying like mad.
They sold their business to Hitachi who fixed the mess.
did this happen to Toshiba and the OCZ drives?
leexgx - Tuesday, November 3, 2015 - linkthe poor power use on that drive is very bad (why i got the BX100 as it has overall best lowest power usage under almost all loads) BX100 is not the fastest SSD drive around but BX200 for £10 more is not good, same with the MX200 as well
coconutboy - Tuesday, November 3, 2015 - linkFor several months now, on a near-weekly basis, Samsung Evo drives are hitting sale prices of ~$150 for 500GB and $75 for 250GB. Except for customers not paying attention, Crucial is gonna have a tough time moving these bx200 when there's unproven reliability, almost no price advantage, and a huge performance deficit.
Crucial needs to drop their msrp or cut retailers a deal to lower street prices.
eek2121 - Tuesday, November 3, 2015 - linkYou are comparing MSRP to street prices. Most of the SSDs in that list are running at least $20 (and sometimes much more) below MSRP. I'm betting $0.25-$0.27 per gig once these things see widespread availability. Don't be surprised if this drive causes price brackets to move again. 480/512 where the 256 was, 960/1tb where the 512 was, etc.
The_Assimilator - Tuesday, November 3, 2015 - linkIt bloody well *better* move price brackets, since it's apparently not good for much else.