The fan sounds loud when the computer is turned on, but it is normal when it is restarted.

At this time, if lubricating oil is not added in time, the fan will be damaged, the bearing gap will be bigger and bigger, and the noise will be bigger and bigger until the fan is scrapped; What's more, the CPU has poor heat dissipation and often crashes or restarts for no reason. More seriously, it may burn CPU. Some friends don't understand that the fan is broken, so they spend tens of dollars or more to buy a new one in the computer market. In fact, they just need to add some oil. The process is not complicated and the effect is remarkable. They can also appreciate the fun of DIY. The steps are as follows: tool preparation: 1, a screwdriver (or two, because it is possible that the fixing screws of the chassis are different from those of the CPU fan); 2. A few drops of lubricating oil (commonly known as "engine oil") (in fact, it can't be so small, because you can't carry it), and it doesn't matter if the viscosity is higher, it will arrive at 100 on the 32nd. If not, use ordinary sewing machine oil, butter (not the kind in bread, but the kind called "calcium-based grease", don't be ridiculous) and molybdenum disulfide. I've used all these. It's okay. Note: Do not use cooking oil. The more you use it, the more sticky it will be, which will affect the normal operation of the fan. After all, it is for eating, not for lubrication. Don't "lubricate" with water. I've seen someone clean and lubricate with water, which almost knocked me out. That man is still an electrical major, so I won't talk about him in 7456. 3, a toothpick (for refueling), of course, use wire or other similar things, as long as you can dip two drops of oil; 4. A brush (if you don't have one, you can replace it with an old toothbrush to remove dust from the fan and heat sink); When the fan is disassembled, you can see that the fan blades and fins are covered with dust. At this time, you need to find a brush to clean up the dust on the heat sink and the fan blades, and uncover the plastic film at the bottom of the fan. Note: Do not completely uncover, only the bearing (yellow part) is exposed, and it is not easy to stick to it after completely uncovering. At this point, you can see that the bearing is dry and there is no lubricating oil. The reason for the noise is that I dipped a little lubricating oil here and carefully dripped it on the fan bearing. Note: just three or five drops, not too much, too much will spill out, sticky, but will stick to dust. In addition, the overflow of lubricating oil will make it difficult to attach the plastic film again. In addition, each drop of oil will make a fan blade rotate several times, so that the added lubricating oil can be wetted in the bearing. Put on plastic film after adding oil. At this time, blow a few breaths on the fan blades to see if they can rotate flexibly. If it doesn't turn, it proves that it is still stuck and needs to be lubricated again until it is completely flexible. You can also use this method if you find that the chassis power fan is ringing. Note: the source of oil is a bicycle repairman with butter. If you ask him for the size of a quail egg, give him fifty cents (too small to get). He must be as beautiful as a fart, so much oil is not worth a dime, but people who buy it in the store don't retail it. The shop that repairs motorcycles and cars must have engine oil. If you want their waste engine oil, take a small bottle to pick it up. It should be free, hehe. Other causes of chassis noise: 1, fan chassis has 2~6 fans, power supply fan, chassis fan (some not), CPU fan, graphics card fan (some not), and North and South Bridge chip fan (some not). First of all, you have to confirm where the noise comes from (this should not be difficult), maybe the noise comes from other fans; In addition, the fixation should be firm, otherwise it will resonate with the motherboard chassis and there will be noise. 2, hard disk The current hard disk noise is generally relatively small. When the old hard disk is turned on, it can hear a sound similar to "filar silk", which is the sound of its spindle motor and cannot be solved, which is a normal phenomenon; Others can hear the sound of "giggle", which is the sound of hard disk reading (writing). Usually, everyone can feel it. After defragmentation, the sound will be lower, but the effect is not significant; If the hard disk reads (writes) loudly, you should pay attention, which may be a precursor to the bad track of the hard disk. If you find that the hard disk is slow to read and write at this time, you should be vigilant and take necessary measures to prevent data loss. It's hard to say that electronic components usually have high-frequency sounds, and some of them have different sounds when running different programs. There is no other way but to replace the parts. I think it's the oscillator inside. Why is the noise still very loud after adding oil? Maybe there is something dirty in your bearing, and there are a lot of it. Although you added oil, it still can't be lubricated effectively, and the noise is still very loud. If you want to solve the problem, you must get rid of the dirt first! You can clean it with kerosene first (of course, you can also use a lot of lubricating oil, but the effect is not good). The cleaning position is the center of the bearing. Blow the blades with your mouth while washing until the fan rotates quickly. Then rub kerosene on the outside, drip lubricating oil into the bearing and seal the protective film. (Do not use strong solvents such as gasoline, alcohol, ether and acetone for cleaning, which may dissolve the plastic shell, especially the enameled wire of the inner rotor, and then lead to the scrapping of the fan. Note: when I say "washing" here, I don't mean washing with high-pressure liquid like washing a car. I just use this word. The operation is nothing more than adding lubricating oil and turning it while adding it until it turns flexibly. $%! #%^! #^