In the current market, mainstream hard drives are mainly divided into solid state drives and mechanical hard drives. Nowadays, solid state drives are basically the first choice, and mechanical hard drives are often used as storage disks. Compared with mechanical hard drives, solid state drives have improved read and write speeds. It is still very significant, and it allows us to really feel the speed experience. For example, when the system is installed in a solid state drive, you can obviously feel that the computer starts up much faster, usually in about ten seconds to complete the boot, and the game The software installed on the solid state drive also greatly improves the loading time and the fluency. Therefore, whether the solid state is the product of choice for new installations or upgraded hardware, why is the price difference of the solid state drive so large? Let’s take a look at the difference between cheap solid-state drives and expensive solid-state drives. I hope you can learn more about solid-state drives through the knowledge of this article.

The difference between cheap solid state drives and expensive solid state drives

1. Brand Differences of Solid State Drives

Why is the price difference of solid-state drives so big? I believe that the first thing you think of is the difference in solid-state drive brands. Brands do affect the pricing of a product. The price of a good brand is indeed more expensive, but the price of a good brand is also more expensive. Reasonable, mainly in the product workmanship and materials are better, the quality control is excellent, the repair rate is low, and the after-sales is relatively complete. The third-line, unknown brand solid state may be poor in quality control, and the main control and particle selection are relatively poor. There are miscellaneous brand masters, defective particles of black and white films, and even particles marked after refurbishment and polishing. The quality cannot be guaranteed , the repair rate is high, and the price is first-class.

But in fact, in addition to the difference in brand, even if it is the same brand and the same capacity, there are many differences in prices, which may be mainly due to differences in read and write performance, particles, main control, and interfaces.

Second, the flash memory particles are different

We may find SSDs with the same brand, the same capacity, and the same interface when purchasing SSDs. However, the price of the SSDs differs a lot, and there may be different flash memory particles. For example, for example, Samsung 860 EVO and Samsung 860 QVO two solid state hard drives with SATA interface. If you don’t understand in depth, you may only find that the colors are different, but there are actually differences in the particles. Samsung 860 EVO uses It is the current mainstream TLC particles, while the Samsung 860 QVO uses QLC particles with a 1TB capacity. The difference between the two is almost 400 yuan because of the particles. Including intel 760P and 660P M.2 solid state price difference is so large, but also because of different reasons.

Solid state drive with SATA3.0 interface with different particles of TLC and QLC

So why do different particles lead to different prices, and what is the difference between them?

The particles mainly include QLC, SLC, MLC, TLC, etc. SLC is used for enterprise-level servers. MLC has gradually withdrawn from the market. At present, the mainstream market is mainly TLC particles, as well as the newly launched QLC particles . The differences between them are as follows.

SLC (Single Layer Storage Cell)

The full name is Single-Level Cell, single-layer electronic structure, each cell can store 1bit data, SLC reaches 1bit/cell, the voltage change interval is small when writing data, the P/E life is longer, and the theoretical erasing and writing times are 100,000 However, due to the highest cost, SLC particles are mostly used in enterprise-level high-end products.

MLC (Double Layer Storage Cell)

The full name is Multi-Level Cell. It uses high and low voltage and differently constructed double-layer electronic structure. MLC reaches 2bit/cell, P/E has a long life, and the theoretical erasing and writing times are about 3000-5000 times, and the cost is relatively high, but It is also acceptable for consumer-level products, and is mostly used in household-level high-end products.

TLC (three-tier storage unit)

The full name is Trinary-Level Cell, a three-layer storage unit, which is an extension of MLC flash memory. TLC reaches 3bit/cell. Due to the higher storage density, the capacity is theoretically 1.5 times that of MLC, and the cost is lower, but the P/E lifespan is relatively low. To be lower, the theoretical number of erasing and writing ranges from 1,000 to 3,000, which is the mainstream flash memory particle currently on the market.

QLC (four-layer storage unit)

The full name is Quad-Level Cell, a four-layer storage unit. QLC flash memory particles have a higher storage density than TLC, and at the same time, the cost is lower than TLC. The advantage is that the capacity can be made larger, the cost is lower, and the disadvantage is That is, the P/E life is shorter, and the theoretical number of erasing and writing is only 150 times.

Which is better, TLC or QLC particles in solid state?

Through the above introduction, we find that the biggest advantage of QLC lies in its lower cost and the ability to make larger capacity solid state drives (SSDs) at the same cost. The capacity will no longer be limited. 1TB capacity is for QLC particles. Basically, it’s trivial. Dozens to hundreds of terabytes are the mainstream, so the solid state QLC particles we see are basically 512GB or above . Small-capacity solid-state drives such as 120G, 240G, 256GB, etc. will basically not have QLC particles. .

Although QLC particles have reduced costs and enabled solid-state drives to quickly enter the era of large-capacity, the disadvantages of QLC particles have led to poor user reputation. The more data stored in each cell of QLC particles, the higher the capacity per unit area. It will lead to more different voltage states and more difficult to control, so the solid state of QLC particles is used, although the capacity is larger and the price is cheaper, but the stability is lower, and the P/E life is lower, and the speed is also the slowest of these particles.

Therefore, QLC particles are undoubtedly inferior to TCL particles in terms of stability, life span, and read and write speed. Compared with the two, TCL flash memory particles are undoubtedly better. But in fact, the reputation of MLC particles in the past is better than TCL particles, but the cost is higher, and manufacturers have gradually eliminated them in order to consider cost factors, so the current MLC particle solid products on the market have basically disappeared. However, with the advancement of technology, TLC granular solid state drives are no longer what they used to be, and both performance and durability have been greatly improved.

Three, the interface is different and the agreement is different

Currently on the market, the most mainstream interfaces of SSDs are divided into SATA3.0 and M.2 interfaces. The SSD and mechanical hard disk interfaces of SATA3.0 interface are the same. We know that the maximum transmission speed of SATA 3.0 channels is 6Gbps. , The maximum actual speed is 560MB/s, which also means that the development of SATA3.0 interface solid-state hard drives on the market has encountered a performance bottleneck! So there is the solid state of the M.2 NVME protocol, which uses the PEI-E channel, which has a larger bandwidth, and the performance has naturally been improved by leaps and bounds.

M.2 solid-state drives look for NVMe protocol!

Also, not all M.2 interfaces use the NVMe protocol to take the PEI-E channel, so when we choose the M.2 interface solid state drive, we must pay attention to whether it supports the NVMe protocol or the SATA protocol. If it is a SATA protocol M.2 solid state drive, the speed is not much different from the ordinary SATA solid state drive, only the interface is different, and the NVMe protocol uses the PCI-E channel, and the current mainstream PCI-E3.0 can provide up to nearly 32GB/ The two-way bandwidth of s, and PCI-E4.0 has doubled the bandwidth compared with the 3.0 specification. Because the PCI-E channel bandwidth is sufficient, the space for improvement is huge and the transmission speed is faster.

Even if it is M.2 NVMe, there is a speed difference!

Maybe we buy a solid state drive with M.2 NVMe protocol, the same brand, capacity, and even M.2 NVMe solid state, we will find that the speed of the label is different, and the price is also different. It is more basic than the M.2 of the entry-level NVMe protocol. The sequential read speed of the solid-state hard disk reaches about 1500MB/s, and the performance of the relatively better ones can even reach more than 3000MB/s. This is the difference between the quality of the master and the flash memory particles , which leads to a big speed difference , and the price naturally has a gap.

This article also does not allow all hosts to have M.2 NVMe SSDs, and more entry-level hosts are completely unnecessary, such as ordinary offices, low-demand homes, and SATA interface SSDs are completely sufficient. You may want to use it. , The entry motherboard may not support the M.2 slot. For productivity, gaming, and performance requirements, it is recommended to use the M.2 NVMe solid state drive. Generally, the current mainstream or above is equipped with the M.2 NVMe slot.

The above is the difference between cheap solid state drives and expensive solid state drives shared by the installer. Why is the difference between the same capacity solid state drives so large? Of course, there are many reasons, such as brand premium, quality of work materials (master control and flash memory particles). ), even different agreements, different channels, there are price differences, it is impossible to sell expensive for no reason, in fact, to put it plainly is the principle of first-class price first-class goods, the water in the computer is very deep, not just solid Hard disks and any hardware in the computer have these problems. If you have time, Xiaolong will help you popularize science slowly. Remember to follow the WeChat account of the “Science and Technology” official account to update more DIY hardware science articles in real time.