SSD storage units have received increasing attention lately and have proven themselves as an essential piece that cannot be overlooked when upgrading or purchasing a modern PC, given the additional features they offer compared to their traditional counterparts. If you feel that your old device is slow and on its last breath, installing an SSD will be like an electric shock to the heart! It will make it work for years to come without any problems.
When purchasing a new SSD, some tend to lean towards units made by Samsung as they are considered leaders in the industry. If you are one of those people, you may have come across the strange symbols QVO, EVO, and PRO written on the units. In fact, each symbol refers to a specific type of flash memory used in the SSD. Keep reading to understand their meanings in detail so that you are well informed about which Samsung SSD unit to choose for your device.
Like any company, Samsung does not put all its eggs in one basket. They categorize the SSDs they offer into two categories: one for individuals or regular consumers like you and me, and the second category focuses on companies, servers, and data centers. In the latter category, Samsung prioritizes data safety, followed by capacity and performance, with price being the last consideration.
Let’s take the 883 DCT SSD as an example. It falls under the second category and uses a special configuration different from units intended for regular consumers. It contains a special engine for Error Correcting Code operation, which enhances its efficiency in dealing with most data loss problems. In addition, it supports Power-Loss Protection technology to maintain the safety of stored data in case of sudden power outage. These are features not found in SSD units intended for home use, as the company focuses on designing them to provide reasonable cost as a priority, followed by capacity and performance, with data safety taking a backseat.
Samsung does not stop at categorizing its storage units into two categories, but each category is further divided into types to differentiate between SSD uses. QVO, EVO, and PRO are different types of Samsung SSD units designed for the first category, ordinary consumers or small businesses, and they are the most common types.
What is the difference between QVO, EVO, and PRO?
As mentioned earlier, these symbols indicate the technologies used in the flash memories used in SSDs. Although you may already know this, SSDs use multiple flash memories called NAND Flash to store data, unlike traditional hard drives that rely on magnetic and mechanical units. NAND Flash memories are based on a transistor known as “the Metal Oxide Semiconductor Field Effect Transistor” or MOSFET, which is the foundation on which flash memories are built and is attributed to the Egyptian engineer Mohammed Atalla in 1959 and is considered the most important invention in modern electronics.
Quick Fact: NAND Flash memories are manufactured based on a transistor called “Metal Oxide Semiconductor Field Effect Transistor” or MOSFET, which is the basic foundation on which flash memories are built, and its invention is credited to the Egyptian engineer Mohamed Atalla in 1959. It is considered the most important invention in modern electronics in general.
The composition of these memories is very complex and difficult to explain in writing. If you wish to understand how they work from the inside, I recommend watching this video from Branch Education channel. In general, NAND Flash memories consist of a large number of cells whose task is to store bits (the smallest part of data: image, video, text file) in the form of electrical charges that organize them as 0 or 1. Not all cells work the same way on all flash memories, but there are different types of them that vary according to the amount of bits they can store. Therefore, the way a cell contains these bits explains how NAND memory works and its name.
In other words, NAND Flash memories in their standard form operate by SLC technology (Single Level Cell), which means that each cell in the memory stores 1 bit, so if data is written on it, it becomes 0, and if it is empty, it becomes 1.
However, these memories have been developed over time to make a single cell capable of storing the largest possible amount of bits. Now we have multiple technologies for NAND flash memories, such as MLC (Multi-Level Cell), which means that a single cell can store 2 bits of data, and TLC (Triple-Level Cell) means that a single cell can store 3 bits of data.
Finally, there is QLC (Quad-Level Cell), which makes a single cell capable of storing 4 bits of data. Currently, the PLC (Penta-Level Cell) technology is being developed, which will make a cell store 5 bits, but reports indicate that this technology will not be usable until 2025.
It is important to understand the above point well because these technologies are what differentiate between SSD units in general or specifically between EVO, QVO, and PRO from Samsung. Now we have 4 types of flash memories, SLC-NAND, MLC-NAND, TLC-NAND, and QLC-NAND.
First: Cost
The price of any SSD is influenced by the type of technology used to store data on it, whether it is MLC, TLC, or QLC. Each NAND Flash chip has different storage capacities according to the technology used. For example, while an SLC NAND chip has a maximum capacity of 128 gigabytes, an MLC-NAND chip can have a capacity of up to 256 gigabytes (twice as much), and a TLC-NAND chip can have a capacity of up to 384 gigabytes (three times as much). Lastly, a QLC-NAND chip has a capacity of 512 gigabytes (four times as much).
The storage capacity of an SSD increases while the number of NAND chips does not. As a result, the cost of an SSD decreases the fewer NAND chips it uses, especially those capable of storing a larger number of bits in a single cell, like QLC-NAND. In other words, the fewer NAND chips used in a single SSD unit, the lower the price.
Therefore, when shopping for an SSD from Samsung, you will notice that despite having similar storage capacities, PRO is the most expensive due to having more NAND chips (MLC or TLC), followed by EVO, and finally the cheapest is QVO from Samsung. The 870 QVO SSD is currently the largest SSD from Samsung (with a size of 8 terabytes) and the cheapest, but of course, this has a significant impact on performance.
Second: Performance
In general, the use of QLC-NAND chips in QVO hard drives makes them the most cost-effective and largest units but with the worst performance. This becomes evident when comparing the speeds between QVO, EVO, and PRO, where PRO performs the best among them, earning the title of “flagship” among Samsung’s hard drives, followed by EVO, and then QVO.
Once again, the reason lies in the technology used between SLC, MLC, TLC, and QLC, as each technology has a different read and write mechanism. For example, in SLC, reading and writing are easy because each cell stores only one bit of data, 0 or 1. In MLC-NAND chips, 2 bits are stored per cell with multiple values – 00, 01, 10, or 11 – making access to the bits in each cell take longer, reducing read and write speeds. The same applies to other chips – TLC = 3 bits and QLC = 4 bits.
As mentioned earlier, SLC hard drives are the fastest, but because they are rare, PRO units from Samsung, which use MLC-NAND chips, are the closest in speed to SLC. Currently, the 970 PRO SSD from Samsung has a read speed of 3,500 megabytes per second and a write speed of 2,700 megabytes per second.
Currently, SLC technology is commonly used for cache memories in SSD units. These memories are small in size but significantly increase read/write speed (as seen in the 980 PRO unit). SLC is used to temporarily store data that the system continuously needs quick access to, while the rest of the data is permanently stored on the underlying TLC or QLC chip.
Read Also: 3 Reasons Not to Upgrade to the Fastest SSD in the World Samsung 980 Pro
Third: Lifespan
First and foremost, it is important to understand that the lifespan of any SSD depends primarily on the number of write/erase cycles it has gone through. The more cycles an SSD has reached, which is determined based on the type of NAND technology used, the closer it gets to its end, meaning it becomes unusable. Cells in SLC-NAND chips have the longest endurance, ranging from 50,000 to 100,000 write cycles, making them work for years without the risk of data corruption. But what about the chips used in QVO, EVO, and PRO?
For MLC-NAND chips, they offer the best endurance with a number of 5,000 to 10,000 write cycles, while TLC-NAND chips allow for approximately 3,000 cycles. Finally, QLC-NAND chips were originally expected to withstand 100 cycles, but manufacturers have managed to increase this number to about 1,000 write/erase cycles.
From the above, we can conclude that the lifespan of PRO units is the longest, followed by EVO, and QVO is the least durable unit in terms of endurance. To prove this conclusion, Samsung supports EVO and PRO units with a limited warranty of 5 years, while QVO units have a warranty of no more than 3 years.
You may be interested in: How to Choose an SSD that is Most Compatible with Your Computer’s Components
In Conclusion: If you want an SSD with a large storage capacity, starting from 1 terabyte, at an affordable price but with lower performance being your main concern, then QVO units will fulfill that purpose perfectly! If you need an SSD that balances everything, such as reasonable price, average performance, large storage capacities, and a long assumed lifespan, then EVO units are the ideal choice. But if you need an SSD that can handle heavy workloads and deliver the best possible performance, I recommend purchasing PRO units from Samsung if your budget allows for their prices.
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