Samsung announced two new client-focused SATA SSDs that will usher in a new era of high capacity and performance. Our review isn't ready due to an unfortunate testing abnormality that we want to investigate further, but that won't stop us from releasing some of our findings now that the NDA has expired, though.
|Product||Samsung 850 Pro||Samsung 850 EVO|
|Capacities||128 GB256 GB512 GB1 TB (1,024 GB)2 TB (2,048 GB)||120 GB250 GB500 GB1 TB (1,000 GB)2 TB (2,000 GB)|
|Interface||SATA 6 Gb/s||SATA 6 Gb/s|
|Form Factor||2.5", 7 mm||2.5", 7 mm|
|Controller||128 GB: MEX256 GB: MEX512 GB: MEX1 TB: MEX2 TB: MHX||120 GB: MGX250 GB: MGX500 GB: MGX1 TB: MEX2 TB: MHX|
|DRAM||128 GB: 256 MB LPDDR2256 GB: 512 MB LPDDR2512 GB: 512 MB LPDDR21 TB: 1 GB LPDDR22 TB: 2 GB LPDDR3||120 GB: 256 MB LPDDR2250 GB: 512 MB LPDDR2500 GB: 512 MB LPDDR2 1 TB: 1 GB LPDDR22 TB: 2 GB LPDDR3|
|NAND Flash||Samsung 3D V-NAND MLC||Samsung 3D V-NAND TLC|
|Sequential Read||550 MB/s||540 MB/s|
|Sequential Write||128 GB: 470 MB/s256 GB: 520 MB/s512 GB: 520 MB/s1 TB: 520 MB/s2 TB: 520 MB/s||520 MB/sBased on TurboWritePerformance|
|Random Read||Up to 100,000 IOPS(QD1) 10,000 IOPS||Up to 98,000 IOPS(QD1) 10,000 IOPS|
|Random Write||Up to 90,000 IOPS(QD1) 36,000 IOPS||Up to 90,000 IOPS(QD1) 40,000 IOPS|
|Power Consumption||Average Read: 3.3 WattsAverage Write: 3.4 Watts||Average Read: 3.7 WattsAverage Write: 4.7 Watts|
|DEVSLP Power||5mW||120 GB: 2mW250 GB: 2mW500 GB: 2mW1 TB: 4mW2 TB: 5mW|
|Endurance||128 GB: 150 TBW256 GB: 150 TBW512 GB: 300 TBW1 TB: 300 TBW2 TB: 300 TBW||120 GB: 65 TBW250 GB: 75 TBW500 GB: 75 TBW1 TB: 150 TBW2 TB: 150 TBW|
|Warranty||10 Years||5 Years|
Undoubtedly, the first thing you will notice is the price. The 850 Pro 2 TB tips the scales at nearly $1,000 or what I call Extreme Edition prices. This model will be a tough sale with Intel's SSD 750 1.2 TB NVMe model being just a used Honda payment away. The 850 EVO 2 TB is a more palatable $799.99, but that isn't why we think the 850 EVO 2 TB is better.
Both new 850 2 TB models use the same Samsung MHX tricore controller and 2 GB of Samsung LPDDR3 DRAM. The 850 Pro ships with Samsung's 32-layer 3D V-NAND MLC, and the 850 EVO ships with 32-layer 3D V-NAND TLC. The TLC model also has an SLC buffer via TurboWrite. Like other EVO SSDs from the company, Samsung scales the SLC portion size in relation to the overall capacity of the drive. With the new 2 TB model, the SLC cache is very large. It's so large, in fact, that we never hit true TLC performance even when transferring a Blu-Ray ISO file to the drive.
In our Computex 2015 coverage, I stated that drive makers would need to mask TLC performance to gain mass acceptance. Samsung managed to do just that with the 850 EVO 2 TB. What end users see is blistering-fast SLC write performance and latency. For normal consumer tasks, that means the lower cost 850 EVO 2 TB is actually faster than the professional 850 Pro. Transfer performance and price are not the only areas where the 850 EVO gets the nod over the 850 Pro.
Notebook users will benefit from the increase in on-battery time made possible by the new 2 TB models. Armed with new low power DDR3, the new drives outperform the previous 850 products in this test. The older 850 Pro and EVO models in lower capacity sizes ship with LPDDR2 that uses more power than DDR3. DDR3 also runs at a higher clock speed so the page table buffer delivers data to the controller faster than before.
The 850 EVO 2 TB is quite possibly the best SATA SSD ever released to the public. In a notebook running on battery power, the CPU, GPU and system bus all run at reduced clock speeds. This causes the whole system to lump around at Pentium III speeds. SSDs accelerate system performance; even older computers benefit from the latency reduction.
The Samsung 850 EVO is so good and has so much pseudo-SLC that the end user almost always writes data at SLC levels. That led to the highest notebook performance score we've ever achieved even though this is the value model. The 850 EVO 2 TB is so efficient that it even performs better than SSDs filled with real SLC, even the one that has my name on it.
You can read our full review of the Samsung 850 Pro and 850 EVO 2 TB models tomorrow on Tom's Hardware.
Update, 7/6/15, 9:45am PT: Fixed typo.