In addition, pay more attention to the inspection machine:

The seal is normal, which basically means that it is a new machine (the most critical step is a good beginning is half the battle)

First of all, look at whether the seal has been moved ~

Some machines have been opened by a hair dryer (that is, after the prototype is put into the original packaging, the sealing is restored)

Traces are sometimes hard to see ~

But what has been opened is opened after all ~

Look carefully at whether the adhesive tape at the sealing part matches the traces pasted when the first box was sealed at the factory ~

If it doesn't match, it's definitely tricky (kraft paper packaging is sometimes better, because it's easy to break the kraft paper on the surface when Kaifeng is used as a prototype, so we should look at it carefully)

And whether there are dust, fingerprints, foreign bodies and the like inside the tape ~

--------The following is a copy:)

First, unpacking-how to judge whether JS brought me a new machine?

Many users and friends don't like unsealed machines when they buy notebooks, mainly because they are worried about repairing machines or being tampered with by dealers and replacing accessories. But in fact, unopened notebooks are often encountered, such as prototypes that have only been placed for a few days, for example, they have just been opened for other users to see the goods, and so on. These situations do not mean that there is something wrong with the machine, and it is a machine that can be purchased with confidence. And the books in those well-sealed boxes are not necessarily unopened, because a ram can completely solve the seal on the outer packaging of the books without leaving any traces. Therefore, when buying a notebook, you should buy a new machine, but it doesn't mean that the notebook that is still attached without a seal must be a new machine, and it doesn't mean that you can't buy a notebook that has been unpacked. The key is to see if the notebook is a new machine. Here are a few tips to tell you if your laptop is a new machine:

1, look at the serial number. Most notebooks should have the same serial number on the body and battery. If the serial number of the battery is different from the serial number of the host, it is very likely that the laptop has been replaced. In addition, when purchasing foreign brand notebook computer products, whether the serial number of the fuselage is consistent with the battery and the outer packaging is a very important basis for testing whether the product is parallel, because foreign parallel notebooks cannot enjoy the warranty in China.

2, look at the anti-theft lock hole. If there is a print, it means that the notebook anti-theft lock has been inserted, and it is very likely that it has been a prototype;

3. Look at the foot. If it is worn and dirty, it means that it has been used and the workbench on the production line is not so dirty;

4. Look at the cooling fan. If the fan blade has a thin dust, it means that it has been used for more than a week;

5. Look at the date of production. The notebook that left the factory three months ago is still on the market, so we should pay attention. The sales of electronic products are very fast, and it is impossible to keep a cost in the channel for so long.

6. Look at the keyboard. The keyboard of the new notebook is clean, but it won't shine. There will be dust in the gap of the used notebook keyboard, and several commonly used keys will be polished;

7. Look at the screws. Let's not talk about this, shall we? Has the screw been removed? Then turn around and go!

8. Look at the gap. Generally, it is difficult to deal with the cracks in the refurbished notebook, such as the small cracks between the AB faces of the notebook screen, such as the cracks in the optical drive, and even the interfaces between the MODEM and PCMCIA card. If dust can be found, it can be sure that it has been placed in the prototype and has not been sealed. What? Also found absorbent cotton silk for wiping the notebook? Do I have to ask what to do?

In a word, whether the notebook is a new machine or not cannot be generalized by whether the outer packing box has been opened. What has been opened is not necessarily a good notebook. On the contrary, the prototype is generally the most reliable notebook. It's a book in good packaging, so be careful to identify it. The most important thing in choosing is to be careful.

Second, the bad point-how much is too much?

A good tool for screen bad point detection -NOKIANtest

LCD screen, the biggest headache when buying a notebook is the bad point. After all, no one wants to buy a new notebook with several bright spots, right? But almost no manufacturer promises that there is no bad point. Among notebook manufacturers, only ASUS promises no bright spots, but you can go to ASUS's forum to have a look. It's just a word game, and it's too dark to stand! Moreover, they call colored points color points, which are not bright spots and cannot be guaranteed, so it is really hard to say what the bright spots are now according to this standard.

The bad point problem of LCD has troubled LCD industry for a long time. Due to the manufacturing technology itself, the bad point of LCD is hard to avoid, but how many bad points are normal? At present, LCD manufacturers have never given a statement about how many bad spots are normal. In fact, the appearance of bad spots is the abnormal operation of a single crystal of LCD, which may be different defects of red, blue and green.

The root cause of bad points lies in production, and it is prevarication to answer them with problems in transit or if they appear after long-term use. Because the bad spots are doomed at the moment when the LCD screen crystal is formed, but some of them do not appear when they leave the factory, or some problems are not serious, and only after using for a period of time will they gradually become dark spots (dark light). In other words, it is very unlikely that bad spots will be produced the day after tomorrow. So buy a notebook with bad points, and don't worry about the spread of bad points.

It's really a helpless topic about the bad points of LCD screen. Generally speaking, when buying a notebook, there are three bad points on LCD screen, especially in area A, so you can refuse to buy it. When choosing a notebook, it is suggested that you can bring some screen testing software to test the screen in detail. Be sure to choose carefully before buying, so as to avoid unnecessary trouble in the future.

Third, the fan-should it turn?

The cooling tool of notebook-fan

The fan of a notebook computer is different from that of a desktop computer, and it is controlled by the temperature of the notebook computer (except for some notebooks with individual desktop CPU). In other words, when the temperature is high, the fan will run faster, and when the temperature is low, the fan will slow down or even not work. This has the advantages of saving electricity, reducing noise and prolonging the service life of the fan. Generally speaking, the speed of notebook fan can be adjusted by adjusting the power saving mode in COMS settings. There are also some notebooks with complete COMS settings, which can directly set the working temperature and speed of the fan. Some friends think that the notebook fan is noisy, so they always want the fan to stop working, and adjust the starting temperature of the fan to be very low, which will overheat the CPU and system, lead to a crash and reduce the service life of related accessories, which is not good. Therefore, it is not good for the notebook fan to turn badly frequently and not work. It is also bad to master a degree.

The general experience is that when the room temperature is about 20 degrees, the room is well ventilated, surfing the Internet and the notebook fan of Centrino CPU should be started every 20 to 30 minutes, and stop working for about five minutes to save energy. When playing games, it starts every ten minutes or so. If the operation has been working crazily at ordinary times, you should check whether there is something wrong with the COMS setting or the temperature control circuit.

Fourth, the keyboard-what is the feel?

Notebook keyboard with Chinese logo

Many friends and some media will talk about how the keyboard of a certain notebook feels in the evaluation of the evaluation room. In fact, this is the most difficult sentence to measure. The keyboard stroke of notebook is much shorter than that of ordinary desktop keyboard, which is very uncomfortable in itself. So it doesn't feel very good. Moreover, everyone has different preferences for the flexibility and hardness of keyboard keys, so it is not objective to say how the keyboard feels based on their own experience.

A good notebook keyboard, to do:

1, a notebook with enough clearance, generally less than 12 inch, often adopts compact keyboard design, and the distance between keys is very close, which makes typing very uncomfortable.

2, the buttons are firm, some bad notebook keyboard buttons, when you press one corner, the other corner will even tilt up, so it is very uncomfortable to type and the buttons are wobbly.

3, the whole is flat, the notebook keyboard is very thin, and accessories such as notebook memory and hard disk are often installed below. Some notebook keyboards are irregularly designed, some places have accessories, and some places are empty. In addition, the keyboard itself has a thin steel lining.

When typing, there will be a sinking feeling where there are no accessories below, which is not only uncomfortable, but even a sense of terror when you press it down or break it. Looking at it from a lower angle, you can even see that the keyboard is wavy and uneven. What's even more frightening about this keyboard is that the high temperature of the notebook will make the keyboard swell up slightly, but when the screen is closed after the computer is turned off, the swollen keyboard has not returned to its original position, but it will rub the LCD screen, causing the LCD screen to be printed with the same scratch as the keyboard layout, which is irreparable and will affect the quality assurance. That would have serious consequences.

4. The layout is poor, the notebook keyboard lacks small numeric keys, and the place is compact, so the layout of the keyboard is different. Some notebook keyboards are designed unreasonably, and some function keys are set everywhere, which is difficult to find and inconvenient to type and use. I used a Toshiba notebook that moved the WIN key to the upper right corner, not to mention how awkward it was.

Fifth, the configuration-see flowers in the fog.

Notebook configuration sheet with flowers in the fog

Many friends often ask me, what is the memory frequency of a certain type of notebook, how many hard disk revolutions, what is the motherboard chip, and so on. I really can't do anything about it and can't answer it. In the current notebook production, due to the inconsistent arrival dates of accessories from upstream manufacturers, and the production line cannot be stopped for materials, it is basically assembled with existing accessories on the basis of configuration that does not violate and is lower than the propaganda commitment. So if the 4200 rpm hard disk installed for the low-end notebook arrives in advance, and the 5400 rpm hard disk installed for the high-end notebook does not arrive, and the high-end notebook has been put into production, only the hard disk is needed, then the 4200 rpm hard disk is installed on the high-end notebook, but the low-end notebook in the later period uses the 5400 rpm high-speed hard disk. So is memory. In this way, there are different batches of products, and the configuration may change. For notebooks that don't publicly promise hard disk speed, memory frequency and motherboard chipset specifications, the manufacturer may make configuration adjustments according to the actual situation, which may be a headache for consumers, but before there is a better solution, it can only be based on the actual spot configuration as far as possible. In particular, it is forbidden to listen to the configuration evaluated by the media and take it as the manufacturer's commitment.

Sixth, the battery-how long can it last?

Notebook battery

The battery life of a laptop is a big problem. If there is no battery, what do we need a laptop for? We might as well buy a desktop LCD computer. What we want is mobility. So what is the standard of battery use? Under what circumstances is it normal to use it for a long time? What are the so-called maximum battery life and standby time? Today's notebook computers are basically using lithium batteries. Needless to say, the benefits are clear to everyone. However, the number of battery cells, the configuration of notebook and the situation of power saving mode have great influence on the service life of battery. Generally speaking, a notebook computer should be able to ensure power supply for more than two hours when the battery power is fully activated and it is running at full speed. It should be noted that the service life of the battery is also seriously affected by the charging and discharging times of the battery. Therefore, it is very beneficial to prolong the battery life of notebook computers to minimize the frequent charging and discharging of batteries.

Seven, down frequency-why did it down frequency?

Pentium m processor with Speedstep energy-saving technology

When some friends buy a notebook equipped with a mobile processor, they are often troubled by a problem, that is, the processor often fails to reach the nominal frequency and always runs at a speed lower than the nominal frequency. Some friends think that there is something wrong with his notebook. In fact, there is no need to be nervous about this phenomenon. Because the processors of notebook products are different from those of desktop computers, most of these notebook processors adopt energy-saving technologies such as INTEL's "Speedstep" and AMD's "Powernow" for the sake of energy saving, and the processors can automatically reduce the frequency of use by analyzing the usage status, thus achieving the purpose of energy saving. If the frequency of use is too low, which affects your use, you can turn off the power-saving option in the BIOS settings and set the attribute of the power option to always be on, so that even if the battery is used, the processor will run at full speed, and of course the battery life will be shortened. After all, you can't have your cake and eat it.

Eight, invoice-should it be?

Invoice for notebook purchase

When many friends buy computers, there is a very confusing question, that is, should they ask for invoices, who should issue invoices for themselves and what is the use of invoices. Invoice is a valid purchase certificate issued by the dealer to the buyer when the goods are traded. Similarly, the receipt stamped with the official seal also has legal effect, which can prove the process of commodity trading. The difference is that receipts can be easily bought in cultural goods stores, or even drawn on a blank sheet of paper, while invoices are purchased from tax authorities by dealers, and after sales, taxes are paid to the state with the invoices. In other words, it is indeed necessary to pay taxes on issuing invoices to users, and it is possible to evade taxes by issuing white notes or nothing. Some dealers say that they can make profits without invoicing, which is precisely for this reason. So why are some dealers happy to invoice users, while some dealers prefer not to do business or invoice users? This is mainly determined by the current situation of our national tax system.

Generally speaking, there are two types of invoices:

1. Machine invoice

2. Handwritten invoice

At present, both are formal invoices, and the tax bureau has not unified them! It's hard to fake the machine! Handwritten as long as the invoice is stamped with the company's financial seal!

Nine, three guarantees-how to package it?

An important certificate of three guarantees-warranty card

According to the National Three Guarantees, notebook products purchased will be returned within 7 days, replaced within 15 days, the whole machine will be guaranteed within one year, and the important parts will be guaranteed for 2-3 years. This is a hard rule put forward by the state for notebook manufacturers, and it is from the perspective of protecting consumers that all enterprises that produce and sell notebooks in China must abide by it. As long as consumers buy notebook products through proper channels, they all enjoy the national three guarantees policy. Some big brands even provide a three-year warranty for the whole machine they produce, which is very beneficial to protect the investment of consumers. After all, there is no problem with the notebook computer at all, and the maintenance cost is not a small sum. But it is worth reminding consumers that parallel notebooks are not within the scope of enjoying the three guarantees of the country.