(a) First of all, all the accessories to carefully check their models and parameters are not what you need, some of the product model difference is very small, but the price is different, functionality and performance is also different.
(ii) second, verify that it is not reworked goods, etc., as follows:
1, the motherboard
Now the DIY market is increasingly hot, the brand's motherboard shipments have increased, even if the quality of the motherboard can not be avoided individually defective, such as the motherboard of a slot soldering, a capacitor or a small device failures, etc., the general in the warranty of the motherboard will be Return to the manufacturer for repair, these motherboards in the repair process is very simple to solve, such as the replacement of a capacitor or small device, in the welded place to replenish the weld, or replace the slot, etc., so that the reworked motherboards and then get in the hands of our consumers, some of our friends do not know how to identify, and some unscrupulous businessmen are the motherboards re-sold to the hands of our consumers, while the more directly to the second-hand market. What's more, the second-hand market directly to the motherboard after processing again package, to the old as new to the market, for such products we will be how to identify it, today I will take you to the first acquaintance with the repair of the motherboard, for your DIY road to bring some help.
(1) generally the most basic identification method is to see whether the packaging of the motherboard is complete, manuals and accessories are complete, reworked motherboards and generally difficult to the box or the warranty card on the serial number on the number! This is the key to identifying reworked products, users should remember this point, when buying computer accessories encountered above the serial number of the case, please be sure to ask the business to give replacement or return! Some users will look at the seal, but I can tell, with a hair dryer to blow the seal hot and then open, we can not judge.
(2) look at the motherboard on the warranty sticker (fragile paper, used to identify the date and business), generally each motherboard on the warranty sticker is no more than two, one is the general agent's sticker, the other is the merchant's sticker, the merchant's sticker will be in the purchase of this motherboard after you post it up, if you find more than one sticker on the motherboard, please merchant to replace the motherboard.
First look at the warranty sticker on the motherboard
(3) The following is a more detailed check, the first carefully observe the motherboard I/O interface inside the dust, mainly to observe the USB.
PS/2 port wear. Because the interface is generally tighter, the keyboard and mouse more than a few times after plugging and unplugging, there is bound to be obvious wear and tear phenomenon, and this kind of wear and tear in addition to replacing the interface, is not repairable, so it is easy to see.
I/O interface oxidation. If the reworked board is used for a longer period of time, the I/O interface should appear to be oxidized, although some rust remover can be used to remove it, but it still inevitably leaves some traces, as long as you look carefully, you should be able to see. This method is also useful for identifying graphics cards and other devices with metal interfaces
Generally, motherboards that have been used will leave a thin layer of dust in the back of the I/O ports.
(4) check the CPU socket near the memory slot and a component below the dust, the machine in the process of prolonged use, due to the CPU fan caused by the surrounding components will accumulate some dust, but the shrewd point of the businessman will use some means to clean, but as long as we are careful, it will reveal the cloven foot.
(5) Check a few screw holes on the motherboard, if the motherboard is used, usually in the screws empty that leaves traces of screws, which is very good judgment.
(6) Finally is to check the solder joints, if the motherboard was replaced, then the solder joints will certainly be newer than the original, you do not look at the solder joints are neat, the general welder for these most basic techniques, are more than enough.
(7) Smell the card's chemical agent odor. New boards are shipped after the process of washing the board. The process is roughly through the use of chemical solvents to wash away debris such as solder left behind when the parts are soldered to avoid short circuits on the motherboard and so on. New boards will generally have a wash board cleaning agent residual chemical odor, with the nose is easy to smell. The reworked board after repair, generally will not go through the process of washing the board, so the normal situation is not that kind of odor, the user in the identification of reworked boards, may wish to refer to this method.
Summary: There is a saying that the road is high, the devil is high. Even if we identify carefully, those unscrupulous merchants will do more detailed, here if you are still skeptical of individual merchants, I recommend that you install the machine, try to go to the store larger reputation of the better merchants, so that we can buy more assured.
2, memory
Memory generally do not have repair goods, because the memory of a bad is basically to be replaced.
You can also check the gold finger wear and oxidation. Memory or graphics cards and other equipment connected to the motherboard through the gold finger, the gold finger by plugging or long-term use, will certainly be subject to varying degrees of wear and tear or oxidation, if you do not re-plated on a layer of only simple use of alcohol and other chemicals refurbishment, it will still be left behind by plugging or oxidized traces of the eye, if the eye is good, it is not difficult to distinguish. However, such as KINGMAX and Kingston and other brand-name memory before the factory needs to be tested, so it will also leave traces of plugging, for such products, we can judge from the degree of wear and tear, or choose to call the anti-counterfeiting phone number for verification.
3, CPU
Bought the boxed, just check whether the boxed on the line.
4, graphics card
(1) to see whether all kinds of accessories are complete, the box or the warranty card on the serial number on the card. Because it is unlikely that the original box will be used when returning to the repair, if you reload the packaging seems too much trouble.
(2) Check whether the gold finger has been scratched, indicating whether it has been used on the slot.
(3) Look at the board to see if there are any obvious manual modifications to the components or capacitors or humps on the board.
(4) See if there are obvious scratches on the graphics card interface, anyway, used plugs can be more or less scratched.
(5) Check the fan and heatsink to see if there is any dust inside. As long as it's used, it's very easy to get dust there in the fan.
5, optical drive
Methods are almost the same, we have to look at the package inside the things Qi Qi, there are no obvious traces of use on the line.
6, hard disk
Today's hard disk prices are getting cheaper and cheaper, the same dealers will be less and less profit, dealers work every day is to try to earn money and earn more money! However, the overall decline in profits makes some JSs have to seek profit growth from other areas, from what? The most common is to repair goods, second-hand goods as new products to sell, we all know that the hard disk can not be compared with other accessories, used or repaired more or less will reduce his service life, so we are buying how to distinguish clearly repair hard disk and second-hand hard disk, became our users must master a skill.
(1) the disk body is most likely to expose the problem
We all know that the current situation of a hard disk problem must be returned to the manufacturer through the counter for repair, so that the counter will be left a lot of reworked hard disk, some JS in order to make money on the reworked hard disk as a brand-new product sold to us, and these reworked hard disk is the users have been used for a period of time, the return of the general manufacturer will not replace the disk body after the factory! After the general manufacturer will not replace the disk body, at most replace the circuit board, so how do we identify the reworked hard disk from the disk on the identification has become the primary means.
Identify these reworked hard disk generally from the hard disk on the screw holes can be found on the problem, has been used in the hard disk, usually on the screw holes will be left on the user screw screw traces, as well as the hard disk on the side of the disk and chassis hard disk rack contact left scratches, if the side of the disk scratches can be covered up, then the screw holes on the traces of the use of the past in any case, can not be covered up.
(2) circuit board hidden hidden
Secondly, we have to turn over the hard disk to look at his circuit board, because some hard disk problems in fact, the disk itself is not a failure, but only a component on the circuit board failure, such as this problem, some of the larger hard disk agent can be resolved by themselves, or return to the manufacturer, the manufacturer is also a direct replacement of the circuit board, or repair.
So we first have to look at the circuit board has not been the second welding traces, has not been replaced by a resistor, etc., and then we have to look at the circuit board connected to the hard disk spindle motor data line interface part of the traces of insertion and removal or blunt force scratches, because the hard disk data line interface is not only very small, due to the internal is to prevent the dismantling of the locking button, so you want to unplug him! It is not very easy, some maintenance personnel will be directly with the cone pliers and other tools, so generally speaking as long as the interface operation, will leave more or less traces, as long as we look carefully, will be found.
(3) PCB metal spacer, oxidation surgery
In addition to the data line interface from the above to see whether the board has been replaced, we can also look at the board from the screws to see whether it has been dismantled, due to the screws on the PCB bit are covered with copper or aluminum design, as long as the screws are unscrewed once after the gaskets on the PCB will be wear and tear, and this wear and tear we do not need to remove the screws can be seen, but we do not need to remove the screws to see that it will not be removed, so we do not need to remove the screws. We don't need to remove the screws to see this, and the screws will also leave traces in the screw holes when the screws come into contact with the screws.
The same method can also be used in the hard disk enclosure, because the hard disk enclosure are processed, long time exposure to the outside world, due to oxidation, the surface will produce a layer of oxide, if the force, this layer of invisible oxidized layer will crack, so the screws and the enclosure contact as well as contact with the cone position will appear a slight "scars", this is not visible if you do not look closely.
(4) the most easily ignored, but the most important
In addition, some second-hand hard disk intentionally has been used for a period of time, although some of the JSs have been carefully processed, but there will always be negligence, although the hard disk as a whole and the same as the new, but some inconspicuous corners will always be exposed to the problem, and here we have to pay attention to the hard disk's power interface, data cable interface, etc., the power interface. Data line interface, power interface due to special, so after using a period of time inside is very easy to produce dust, and some JS will ignore this is not too good to clean up the unknown, we mainly need to look at the power interface, there is no dust and power interface contact scratches, inside the contact point there is no use of traces, and so on.
For the SATA interface hard disk we are more easy to view, due to the interface of the special, SATA hard disk data interface are exposed to the outside of the interface of all the gold finger plating treatment, so as long as the data line and the data line after contact with the gold finger is bound to leave abrasions, the same method is also suitable for us to identify the memory of the graphics card and other products.
(5) Warranty labels to see clearly
In addition to the hard disk itself, we also need to look at the hard disk on the label is intact, whether there is a phenomenon of covering changes, because the general manufacturer to return to the hard disk will be re-posted a warranty label, or maintenance label, for the labeling of the distribution counter is not afraid of damage, as long as the damage is not continued after the manufacturer warranty, general The JS will use its own warranty label to cover up the manufacturer's label, while the general first-hand counters sell products are only a label.
If a hard drive has more than two warranty labels, you can at least say that the dealership is not a one-stop shop, it's a speculator from somewhere else, or that the hard drive has been sold once but was returned.
(6) Check to see if the drive has been partitioned, and use HDtune to check the usage time of the drive.
In short, not only when we buy a hard disk, we buy other products, too, must not ignore some details, because these details are most likely to be ignored by us is also the most likely to be ignored by the dealer, if you can find these details, then we buy products JS come up with a second-hand or repair goods and then fool us that this is a new product, we can immediately walk away. We can immediately go away, not on him at all.
7, power
View whether the packaging is intact, the general power supply will be wrapped in a layer of film to see whether the screws above the traces of open, labeling there is no damage. The fan has no dust and so on.
8, monitor
Look at the packaging has not been opened, accessories Qi Qi, screws have not been open, the interface has no wear and tear, there is no dust, the LCD screen is not above the obvious fingerprints or scratches, the use of the machine will certainly be left with fingerprints or scratches, with the LCD test software to see if there is a bad point, and so on.
(1). The first thing we encountered is the "point" of the problem, now some products are packaged by the manufacturer of bright spots. We have to ask clearly, the product is not a package of points, is a package of bright spots or all the points, how to package (is found in the store is counted, or in a period of time is also counted)? What are the accessories? If this product is no package point guarantee, then we can negotiate with the business, plus wallet points is not a good way, then if the business allows you to pay to open the box to try the machine, then you have to be careful, this link is very easy for you to be cheated, I have a colleague, that is, in the purchase of LCD, to try the machine business let him pay, the results of his honest payment, the results found that there is a bright spot! 1 bad point, the business to the national standard "bright bad point of 5 or less for qualified products" as the reason, refused to refund him, let him on a big time, so, in this step, we have to be very careful, determine the conditions, try the machine after the satisfaction of the payment, so as to maximize the protection of their own interests.
In the selection of LCD monitors on this bad point, bright spots, dark spots three kinds of point defect detection is very simple. The most common method is - mouse right-click on the desktop, select "Properties", in the open window, select "Appearance", and then in the "Color" column, select "Black" or "White", and then click "Apply". In the desktop black or white or red, green, blue background to carefully observe the LCD screen with or without color points or light-emitting bright spots, if there is a point of the LCD screen defects. It is best to ask for another one before the payment is completely free of such defects or point defects in the screen on all sides of the product. We can also use software to detect these point defects, DisplayX is a monitor software only 48KB in size, no installation, unzip and run the main program. Click "General Full Test" can complete all the tests, including interlacing, solid color, color, convergence, geometry, breathing effect, 256 levels of gray, grayscale, contrast and other test items, right-click the mouse or press the Esc key to exit. And to bad point test, just in the "General single test" menu, select "solid color" mode, click the mouse to enter the full black, full red, full green, full white, full blue and other different solid colors, it can be very easy to find the LCD screen on the bad points, bright spots and dark spots. I buy LCD, like to use a USB flash drive to this software and a few familiar with their own colorful pictures, plus a high-definition video, these tried, basically can be said to be "point" and color performance is no problem.
(2). Warranty is also a very important issue, some products are now warranty three years, but his screen is only guaranteed for one year, so we have to do our homework before we buy, to find out what the product warranty? Those who are not guaranteed? There is the invoice problem, now some manufacturers lease invoice to warranty, so we buy before, it is best to figure out the problem, if there is no clear question can call directly ask the manufacturer, which is necessary to protect their interests.
(3). New or old machine, some unscrupulous merchants, the prototype will be boxed and then sold, or will be stolen from the box of accessories, so when you buy a monitor, be especially careful to pay attention to whether the monitor has been opened, especially below the seal (merchants are generally open below, and to show you must be the top of the), double-sealed packages must not be, if the seals are not neatly, there is a great deal of suspicion, the original monitor Complimentary DVI cable were taken away by JS, unaware of the case will be on the pawn, open the seal of the monitor is relatively easy to recognize, the method is very simple, first look at the seal: the original seal is very neat, the two ends of the use of a special cutting tool to cut, usually very straight or the rule of the jagged is very easy to identify. Secondly, look at the box: the edge should be intact, there is no trace of the skin being torn. If the above two are intact, then the possibility of being unpacked is very small. But sometimes dealers will use the hair dryer method to open, open the box, they will use a hair dryer to blow hot air against the seal beforehand, the seal will be softened and then opened, this method of opening the box appearance is relatively neat, if the seal is pasted with care, it is not easy to identify. After opening the box, we must pay attention to carefully observe the monitor is intact, whether there is dust, fingerprints and other traces of use on the casing, be careful of the business prototype after sealing the box and then sell it to you, there is another way, is to smell, generally new machines in the first use, due to heat will have a general taste of plastic, this is also a way to identify whether the new machine.
(4). Do you have all the accessories? When you buy, you should check whether the accessories are complete, the easiest way is to look at the inside of the packing list, one by one control, to avoid merchants to steal the DVI cable and other accessories.
Finally, is to ask the business to open a ticket, the model and warranty and other information listed, and stamped on the business, so as to protect their own interests are not infringed upon, and finally, of course, is to pay the money la, or not to people as a liar to fight out ah .
(5) connected to the power cord and video cable, power on the test machine. At this point, buyers should first look at the LCD screen light is uniform, whether there is a district part of the polarized light or the edge of the position of light leakage. Then we should look at the liquid crystal in the display, whether the image has a frequent correction of the situation. If the above two phenomena in the LCD comes with the relevant control buttons to adjust (first select the automatic adjustment, and then set manually), still did not eliminate, it is best to ask for more another spot.
(6) If you want to buy DVI cable to pay attention to the interface with different, because DVI has DVI-D and DVI-I two specifications, their interfaces are different. Be careful to observe.
Note: Other accessories are probably these methods can be recognized
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