Best SSDs For The Money: August 2012 (Archive)

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Can someone explain to me what the big difference is between the Samsung 840 Pro vs 840 EVO?Is it just the higher average data rate?It's confusing that the sequential data rate is higher on the EVO, yet the Pro is substantially more expensive.Is there something else I'm missing here? Considering purchasing my first SSD here.
 


The main difference between the 840 Pro and 840 EVO, as someone else already stated, is that the EVO uses TLC (Triple-Level-Cell) NAND Flash Memory whereas the Pro only uses MLC (Multi-Level-Cell) NAND Flash Memory. The extremely simplified version of what this mean is: TLC is more compact (you can fit more data on the same sized chip) while MLC is more reliable.

Western Digital released a white paper that includes a detailed explanation of what this means (along with what SLC (Single-Level-Cell) NAND Flash Memory is).

In a nutshell:
How a HDD works: magnetic cells are changed to indicate either a 0 or 1. Each cell stores one bit of data.
NAND Flash: Cells are given a set voltage to hold.
SLC: Each cell can have two different voltage states, leading to each cell holding either a 0 or a 1 and containing only 1 bit of data.
MLC: Each cell can have 4 different voltage states. This allows each cell to hold two bits of data as the states can reflect either a 00, 01, 10, or 11 state.
TLC: Each cell can hold 8 different voltage states. This allows each cell to hold three bits of data and the voltage states can be used to reflect a 000, 001, 010, 011, 100, 101, 110, or 111 state.

Why is reliability affected? Each cell in NAND flash has the same voltage capacity, regardless of whether it is SLC, MLC or TLC. Imagine this capacity is 1 volt.

In SLC memory this leads to each cell to be holding either 1 volt or 0.
In MLC memory, this means each cell will either have a 0, .333, .667, or 1 volt reading, with each voltage representing a different data state (00, 01, 10, or 11).
In TLC this means each cell with be holding either 0, .143, .286, .429, .571, .714, .857, or 1 volts, with each voltage level again representing one of the data states (000, 001, 010, 011, 100, 101, 110, or 111).

As you can see, the difference between the voltage levels gets closer as you increase the number of bits in each cell. The SSD controller reads the voltage of a cell and translates that into usable data for the computer, but as the voltage states get closer together you increase the risk of a read (or write) error if the voltage level is just a little bit off.

I hope that helps a little bit in your understanding of the difference between the 840 EVO and 840 Pro. if you want more detailed information the the WD whitepaper I linked is a great resource.
 


Ok if I understand what you are saying (and I did skim that article), MLC is more expensive to manufacture, and in theory lasts longer? So the TLC is cheaper to manufacture but as a result of the increased voltage in/out it also will fail sooner?

Are the SLC SSDs exponentially longer-lasting?

I have a western digital caviar black that runs great. I'm a gamer, and I don't mind the 30 second boot up speed. To my understanding, generally speaking the SSDs don't improve game performance except for MAYBE level loading by a few seconds.

Every time I look into SSDs and see that they don't last near as long as mechanical drives, and that the new SSD manufacture process is heading towards faster speeds and drives with a SHORTER lifespan - I just end up thinking I should stay with my 1TB mechanical drive.... At the same time I like fast and SSD sounds good, but I would be kinda pissed if the drive failed in 1-2 years and I lose all my unsaved stuff....
 
Bottom line: I don't ever recommend replacing the HDD with a SSD in your primary computer. The only time I personally would run any PC with only a SSD is it was a laptop and my secondary system, meaning all my data was stored on a different PC and replicated on a third unit (NAS or external HDD).

That said, the benefit received from a SSD is very real, not in FPS performance, but in all your boot and program load times. You want a computer that feels fast? Tired of waiting for any program (OS, Application, Game or other) to load? Move to SSD. The best way to do this in a primary computer is grab a 128 or 256 GB SSD and use it to install your OS and all your games/applications. Format an internal HDD and, during the OS install process, relocate the location of your "Users" folder (in Windows Vista and later) to the mechanical (usually D:) drive. You will absolutely notice a performance difference in my experience and you don't have to worry about losing data. You should still obviously have a second drive (External or NAS) to save backups of all your data, but in a worst case scenario if your SSD fails then all you lose is your installed programs. As long as you still have the installation media then you haven't really lost anything except the time it takes to reinstall.

As far as realistic lifespans on SSDs, 1-2 years is not at all what I've heard. Everything I've read indicates that any decent quality SSD should be expected to last at least 5 years (give or take) in a real world scenario. The average lifespan of a mechanical HDD is 7 years. So we aren't looking at a crazy difference here.

Additionally, SSDs that use TLC weren't really around (for sale at least) because manufacturers are not going to put out an unreliable product. SSD technology is still very much developing and as time goes on a lot of this development is in the area of data reliability. 24, or even 12 months ago for that matter, you didn't really see TLC drives for sale. Improvements have been made to their reliability, however, so that they are now starting to get to the point where manufacturers are trusting them enough to put them on the market. Samsung is hands down one of the best quality SSD manufacturers out there and has definitely done a lot to earn the trust of consumers as far as their product reliability and durability goes. While I personally will be installing a Samsung 830 (already ordered long ago and no longer on the market as it was replaced by the 840 Pro) and choose to shy away from TLC SSDs, I would absolutely be surprised if I started hearing about worrisome reliability issues with the 840 EVO.

The top two drives I personally considered when I was waiting for a deal to buy an SSD for my next build were the Samsung 830 and Mushkin Enhanced Chronos Deluxe (non-Deluxe version has lesser performing parts).
 
???? ???????, ? ??????? ????????? Cinema 4D ? After Effects, ? ???? ???????? ????? ????????? ??? ?????? VFX 3D Render, ? ???? ?????? ??? ????? ????? ????? ????????????? ??? ????? ??? ??????, ? ????? ??? ????? ???? ????????????: 1.Motherboard-ASUS Z9PE-D16/2L SSI EEB Server Motherboard Dual LGA 2011 DDR3 1600 2. CPU-Intel Xeon E5-2620 v2 Ivy Bridge-EP 2.1GHz 15MB L3 Cache LGA 2011 3. Case-Cooler Master Cosmos II 4.Cooler-SeaSonic X Series X-850 850W ATX12V v2.3 / EPS 12V v2.91 SLI Ready CrossFire Ready 80 PLUS GOLD Certified Full Modular Active PFC Power Supply New 4th Gen CPU Certified Haswell Ready 5.HDD-Western Digital WD VelociRaptor WD5000HHTZ 500GB 10000 RPM 64MB Cache SATA 6.0Gb/s 3.5" Internal Hard Drive Bare Drive - OEM 6. SDD- SAMSUNG 830 Series MZ-7PC128B/WW 2.5" 128GB SATA III 7.GPU-NVIDIA® Quadro® K4000 VCQK4000-PB 3GB GDDR5 PCI Express 2.0 x16 Workstation Video Card 8.Display-ASUS VS24AH-P Black 24" 5ms (GTG) HDMI Widescreen LED Backlight LCD Monitor IPS 300 cd/m2 80,000,000:1
 
I must say that as much as Tom's is into charts and graphs, there is no chart as to how much over provisioning, read-write MTBF, etc. I would like to know if all mfg's use the same amount of over provisioning. And I would like to know who's failing early and who isn't.Those really count to me since this is a new area, and I don't want to buy a lemon because I didn't know any better.
 
Couple of points to note: The performance graph of the mushkin USB SSD has really weird keying. Wouldn't it make more sense for solid/dotted to refer to repeated/random and orange/green to refer to read/write? The current situation is a bit annoying, as the choice of dotted/solid swaps between read and write.Also, OPAL isn't that big a deal. Most modern CPUs (excluding the low-end ones, where you're less likely to be using an SSD) have AES-NI support anyway. The only time I can think of would be a drive with compression, e.g. Sandforce-based, and only if it was compress-then-encrypt.
 
It would be interesting to see data on $/Gb. Especially considering the wide variety of storage capacity in your chart.Otherwise, great article from T.H. as always.Thanks.
 
im between the kingston hyperx 3k 120gig at 90 dollars and the intel 530 120 gig ssd for around $14 more the kingston is faster but the intel offers the 5 year warrenty (although you pay extra for it) tough desicions! i guess the crucial got on the list because it is 5 dollars less than the kingston but honestly i think the kingston is probably better. thoughts?
 
I feel like you guys should also put Price per GB. Even though you can find it on other sites to find out i just feel like it would just be helpful having it all there(maybe put it under the performance per dollar)
 
Umm just to point out that OCZ haven't used sandforce for some time seeing as they own indilinx....which the OCZ vertex 4 is running on. I've had my OCZ vertex 4 now for a little under 2 years and it is flawless not a single fault since I installed it in my system. Boot to windows is under 6 secs. I first got a little 60gb petrol drive just to see how it performed as an SSD convinced me to get a better one but that little drive which gets very mixed reviews is still working just fine.Perhaps some of you are doing something wrong which is damaging the drives. It really wouldn't surprise me that much.
 
This list is a little bit shaddy. I have a ADATA sp900 256mb and it performs better the a plextor or samsung in read/write. all my friends talk about the amazing samsung ssd. and the Adata disk cost much less then the samsung, remeber you pay the name samsung 2.
 


you'd be amazed how many people have their SSDs configured wrong. For my money the best two of the best three SSDs out there are Samsungs.
 
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