If the key parts hang up, for example, CPU⑾ will cut and blow the mold, swing Xing Yunjiu's window and let him swing the ebug card.
Don't underestimate this guy, in fact, the working principle of the debugging card is still relatively advanced. After the card is turned on, it will detect whether there is data written in the 80h address. Whenever there is data written in BIOS for 80h, it will be grabbed, and then it will be converted into binary code through decoding, and the code of 16 will be displayed through digital diode. Here are some common values:
First of all, if FF is displayed at the beginning, it means that your machine is seriously down and BIOS can't execute POST.
If it stops at 04, C 1, it must be a memory problem. You can consider whether the overclocking is a bit high or the particles on note are not good.
If 7F is displayed, it depends on whether there is something wrong with your graphics card, whether it is not inserted tightly, or whether the video memory frequency is too high, which leads to data rewriting.
There is also a very important code, 05. I don't think ordinary meticulous comrades will have this problem. This code means: initialize the keyboard and clear the screen. This code will be displayed if the keyboard is not plugged in (the keyboard is broken) or the keyboard controller on the motherboard is broken.
I think the cruelest code is 0 1~02. Why do you say that? Think about it. Generally speaking, what are the most important and critical components on a PC? Yes, it is the CPU. There are several steps to detect CPU. Where 0 1 is to detect the state of CPU, which is set and detected by BIOS. If there is no problem, it will set all states to off and pass the test.
02 code is to detect the various registers of CPU. Personally, I don't usually get stuck in this item.
For motherboard testing, use 03 code. At this point, NMI, PIE, AIE, UEI, DMA ... reset floating-point arithmetic unit, temporary page storage, initialize timer, initialize DMA controller and interrupt controller ... Anyway, there are things on the motherboard, and all functions are basically repeated. However, if the card really shows 03, it must be said that the board is broken. But it is difficult to determine what is broken on the chessboard. The problem is probably a chip of the North-South Bridge.
Finally, after a series of digital displays, it stays on FF, so congratulations, there is nothing wrong with your machine, because FF is a code written for 80h.
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If the computer can tell us where the fault happened, wouldn't it save time and effort and take a lot of detours? In fact, as long as you can make good use of the debugging diagnostic card, everything will become relatively easy.
I. Working principle of debugging the diagnostic card (Figure 0 1, Q7Q-2- 1 debugging card)
Debugging card is a test card that can detect computer faults. There are two PCI and ISA interfaces to facilitate the use of different types of motherboards. When the debugging card is inserted into the PCI or ISA slot, when the computer is started, the display screen on the card will display various codes according to the startup progress.
After the motherboard is powered on, first test the CPU to see if its internal registers are normal; Then the BIOS will detect all other registers in the CPU to determine whether it is correct; Then detecting and initializing the chipset of the main board; Next, check whether the refresh of dynamic memory is normal; Then clear the screen to a black screen and initialize the keyboard; Next, check the CMOS interface and battery status. If a device fails to test, the system will stop and start, and the code displayed on the debugging card will not change. In this way, by querying the hardware corresponding to the code according to the specification, we can easily determine which component the fault may occur on. Because the price of DEBUG card is not high (about 15 yuan), it has become one of the necessary tools for many DIY enthusiasts.
Second, the actual use of debugging diagnostic card
The use of debugging cards is also very simple. The following discusses the solutions of several common fault codes. It should be noted that at present, most motherboards in the market use AWARD BIOS or AMI BIOS. Because the current debugging card actually calls the self-checking process of the motherboard BIOS, different motherboard BIOS programs display different codes, and the methods to solve the problem cannot be generalized. So we also discuss it in two parts.
The following instructions will select the most common fault codes and their solutions. For other more detailed code meanings, please refer to the instruction manual of the debugging card.
1. Bonus BIOS
Error code: 00(FF)
Code meaning: The motherboard does not perform normal self-test.
Solution: this kind of fault is troublesome, and the reason may be that the motherboard or CPU is not working properly. Generally, in this case, you can first remove all the components on the computer except the CPU, and check whether the motherboard voltage, frequency doubling and external frequency settings are correct, then discharge the CMOS, and then turn on the computer to check whether the fault is eliminated. If the fault still exists, you can also take the CPU out of the socket on the motherboard, carefully clean the socket and the dust around it, then install the CPU with a certain pressure to ensure that the CPU is in close contact with the socket, and then install the heat sink before starting the test. If the fault still exists, it is recommended to replace the CPU test. In addition, the motherboard BIOS damage will also cause this phenomenon. Refresh the motherboard BIOS if necessary and try again.
Error code: 0 1
Code meaning: processor testing
Solution: Explain that the CPU itself failed the test, and check the CPU related equipment. If the CPU has been overclocked, please restore the CPU frequency to the default frequency and check whether the CPU voltage, external frequency and frequency doubling settings are correct. If all normal faults still exist, you can replace the CPU and try again.
Error code: C 1 to C5
Code meaning: memory self-test
Solution: Common fault phenomena generally indicate that there is a fault in the memory of the system. To solve this problem, you can dust and clean the memory first, and then test it. If the problem still exists, try to clean the golden finger with a soft eraser until the golden finger appears metallic luster again, then clean the sundries in the memory stick and check whether the metal shrapnel in the memory stick is deformed, broken or oxidized and rusted. If the fault persists after starting the test, please replace the memory and try again. If there are multiple blocks of memory, you can find the fault by replacement.
Error code: 0D
Code meaning: video channel test
Solution: This is also a common fault phenomenon, which generally means that the graphics card test is unqualified. Check whether the connection between the video card and the motherboard is normal. If the video card is found to be loose, it should be reinserted into the slot in time. If there is no problem with the contact between the graphics card and the motherboard, you can remove the graphics card to clean up the dust on it, clean up the golden finger part of the graphics card, and then plug it into the motherboard for testing. If the fault still exists, you can replace the video card for testing.
Generally, the display signal will be transmitted to the display after 0 days of system startup, and the indicator light of the display will turn green, and then the debugging card will continue to jump to 3 1, and the display will start to display self-checking information. At this time, the computer fault can be judged by the relevant information on the display. ]
2.AMI BIOS article
Error code: 00 (or FF)
Code meaning: The motherboard does not perform normal self-test.
Solution: (same fault code as the winning BIOS)
Error code: 0 1
Code meaning: processor register test
Solution: (same fault code as the winning BIOS)
Error codes: 0D to 0F
Code meaning: CMOS stops register read/write test
Solution: Check the CMOS chip, battery and peripheral circuits. You can replace the CMOS battery first, then clean the pins and circuit parts of CMOS with cotton balls dipped in anhydrous alcohol, and then see if the problem is solved after booting.
Error codes: 12, 13, 2B, 2C, 2D, 2E, 2F, 30, 3 1, 32, 33, 34, 35, 36, 37, 38, 39 and 3A.
Code meaning: test the graphics card
Solution: This kind of fault is very common in AMI BIOS. You can check whether the video interface circuit, main chip and video memory of the graphics card can't work because of too much dust. If necessary, you can replace the graphics card and check whether the fault is solved.
Error code: 1A, 1B, 20,21,22.
Code meaning: memory test
Solution: It is the same as the solution of memory failure in Award BIOS.
Note: If it is set to no error in BIOS settings, the diagnostic card will not stop displaying fault codes when it encounters non-fatal faults. The solution is to set the BIOS settings to prompt all errors before starting, and then diagnose according to the debugging code.
Third, pay attention to the limitations of debugging cards.
Although the debugging card can intuitively point out the failure possibility that the system can't start, the tool is a tool after all, not a panacea. When using the debugging card, we should also pay attention to several aspects.
First of all, due to the limitations of the debugging card itself, sometimes the fault code displayed by the diagnostic card can not reflect the real fault of the computer, especially the debugging card with PCI interface. Because the address line and data line of PCI are used for * * *, whether the current signal is address or data can be distinguished by 10 pulse time, so it is possible to generate error code in diagnosis. So don't believe all the error codes on the debugging card.
Secondly, in the process of using the debugging card, sometimes the code cannot be displayed completely, that is to say, the code displayed by the debugging card remains unchanged after a certain startup stage. This kind of fault often occurs on debugging cards using PCI interface. In this regard, you can try to replace the PCI slot or use ISA slot to solve it (most debugging cards have dual interfaces of PCI and ISA).
Third,
Overclocking with debug card:
In the past, when overclocking appeared black screen, we couldn't be sure whether there was something wrong with the memory, AGP graphics card or IDE device, so we had to plug in this and pull out that based on our own experience, and the result might still be in vain. Now, just look at the code displayed on the postcard to determine the problem.
My PC motherboard is upgraded to BE6-II, the CPU is Celeron II533, and the memory is LG's PC 100 128M. Insert the debug card into the motherboard and perform the following overclocking test.
Start the machine normally at the external frequency of 66MHz, turn on the power supply, and all the LED indicators of the power supply are on, which proves that there is no problem with the power supply and other LED indicators are in normal condition. The reset indicator light keeps flashing, and the number displayed on the digital tube keeps changing. Finally stay in "FF". After the system self-check, everything is normal.
Celeron Ⅱ 533 (66.6× 8 = 533) has certain overclocking ability, and the frequency doubling is locked, which can only exceed the external frequency. If the external frequency exceeds 100, that is, the main frequency of 100× 8 = 800, it can't be started normally, the display doesn't respond, and the digital tube displays the self-test code "0D", which is known from the manual. It can be seen that things that are not easy to understand at ordinary times can be easily judged by debugging cards, saving a lot of time and learning a lot of knowledge.
If it continues to exceed 1 10MHz, it can't be started. The self-test code is always "FF", which means that the CPU doesn't work at all. Set the CPU voltage to 1.7V, it can be started smoothly, run large programs, and the CPU temperature has not changed. Finally, set the external frequency to 133MHz. No matter how the voltage is applied, "FF" will always be displayed when the computer is turned on, indicating that the external frequency of 133MHz has exceeded the limit frequency of our CPU. With the help of Debug card, it took only ten minutes to determine the overclocking limit of CPU, which was difficult to do before. This card is obviously a powerful auxiliary tool for CPU vendors and many installers.
Fine-tune memory parameters with debug card;
When overclocking, memory is an important factor affecting overclocking performance. Debugging cards can also help us test the overclocking limit of memory. For LG's PC 100, let's say CL=3, which all pass from 100MHz to100 MHz. Ok, let the memory frequency increase by 33MHz above the external frequency (supported by the motherboard), and the external frequency will still start from 100 MHz until 168. It passed normally, but when it reaches 120MHz, that is, the memory frequency is 152MHz, it cannot be started. The self-check code shows "c1"-"memory detection error". It seems that 147MHz is the limit of memory. Similarly, if you change a PC 133, the frequency can reach 160MHz. Then set the CL value to 2. As a result, neither memory can be turned on normally at the original limit frequency, and the display is still "C 1". When the frequency of both memories is gradually reduced, it is found that the memory of PC 100 returns to normal when it is at 1 10MHz, while the memory of PC 133 is now reduced to its standard 13.
In a word, any excellent tool can only help us solve problems, and we can't rely too much on it. After all, at the last minute, all computer failures still have to be solved by our own ability. Being good at using tools and exercising our DIY ability is the most fundamental way for us to solve computer faults.
About the code, still have to study hard!