Problem Description:
Some computers that have been in use for a little while always have BIOS reset problems, and all the original settings in the BIOS are lost.
Solution: (you can follow the steps below to check one by one)
1, may be the CMOS battery on the motherboard is not enough power, in this case try to use the "multimeter" to measure the CMOS battery power is > 3V, such as the voltage > 3V indicates that the power is normal, such as the voltage < 3V indicates that the battery is under-voltage, you need to replace the battery to solve the problem.
If you don't have a "multimeter" at hand, please disassemble the machine after powering off to confirm the type of CMOS battery on the motherboard, confirm whether the CMOS battery on the motherboard is with or without wires, and then purchase the matching CMOS battery for replacement test.
PS: For the battery with cable, please make sure the positive and negative poles of the cable match the original CMOS battery, if the positive and negative poles don't match, it will also lead to failure to save CMOS parameters.
2, check the jumper
Some models of motherboards are designed with a jumper to clear the contents of CMOS, if this jumper is inserted incorrectly, or the jumper cap comes off, then the BIOS naturally can not be saved, and will be cleared once every time you turn on the computer. Check the specific operation method of the jumper can consult the hardware supplier;
3, Check the CMOS battery holder shrapnel or CMOS battery connection end
Although the battery has been replaced with a new one, it is also possible that the battery holder has failed, causing the battery not to supply power to the motherboard at all. We need to carefully check the battery holder on the motherboard, especially the bottom of the shrapnel. Make sure the tabs are flexible enough to make good contact with the battery. For CMOS batteries with connecting cable, check that the CMOS battery cable on the motherboard is properly plugged into the CMOS battery pins on the motherboard.
4, static interference
It is also possible that the motherboard has accumulated a lot of static electricity, causing interference with the motherboard line. We can find a grounding wire, fixed in the chassis shell grounding, release static electricity.
5, check whether the motherboard leakage
After the motherboard is turned on, the daily use of all normal, so the motherboard failure of this piece we do not consider for the time being. Has been used for many years of the motherboard, there may be some components there is a leakage phenomenon, for which we recommend removing the motherboard, in the screws below the mounting holes on the pad some insulating rubber pads.
If the above steps are troubleshooting, but still can not solve the problem. Then it may be the motherboard south bridge, EC, BIOS chip, CPU damage, you can find maintenance personnel with a heat gun for heat treatment. Or contact the hardware supplier to send back to the original factory for testing and repair.
