Detailed introduction to CPU overclocking problems and solutions

CPU overclocking is also a long-standing problem. Many users will encounter such a situation, but basically we will not solve this situation because there is too little understanding of this problem. Now give it first. Everyone introduces what is CPU overclocking

First, the history of overclocking

In the era before 486, the CPU uses a unified frequency design, the frequency of the central processor is the frequency of the motherboard, the chipset The memory and cache are all running on the same frequency, so there is no multiplier jumper on the motherboard, and each motherboard is only suitable for one CPU. Overclocking can be achieved by increasing the frequency of the crystal oscillator on the motherboard. The earliest overclocking record for the Amiga 500 Motorola chip is from 9MHz to 12MHz, and the Intel 80286 is from 8MHz to 12MHz.

Later, Intel introduced a multiplier CPU. Some motherboards began to be compatible with more than one type of chip. At that time, there was no official documentation at all. We can only rely on experience to determine which pin is multiplying. The line is soldered to overclock, just like the recent K7.

The first leap forward in overclocking history was the emergence of the Pentium chip. Almost all Pentium 75s can exceed 90MHz, and the overclocking revolution began to take place worldwide. Subsequent 133 Super 166, 166 Super 200, 233MMX Super 266 can only improve one to two levels, the highest is only four.

When the wheel of history advanced to the Celeron era, the most brilliant overclocking era finally arrived. The first was the unbuffered Covington Celeron 266 Super 400, followed by the biggest breakthrough in overclocking history ——300A 450MHz, it improves the performance of the CPU by a full 50%! And the probability of overclocking is very high, the average of two CPUs can only be super. In Celeron, the last chip that can stabilize overclocking is 366,366. The performance gain of 550MHz is 183MHz, which is the highest level that can be achieved by air-cooling and no voltage overclocking. Today, the most promising overclocking chips are the PIII-500E and PIII-600E, which both increase the main frequency by more than 200MHz.

Second, bus speed and multiplier calculation

486DX2 is the first multiplier CPU, 2 of which means double frequency, main frequency = FSB & times; multiplier, 486 The external frequencies of DX2/50, 66, and 80 are 25, 33, and 40 MHz, respectively, and the chipset and memory work at 1/2 clock of the main frequency. Due to the speed limit of sound card, video card, hard disk, optical drive, memory, etc., we can't increase the FSB infinitely, only the multiplier. Today's CPU has reached 10X FSB, which means that the processor is ten times faster than the bus.

After the overclocking method is widely circulated, the free conversion of the FSB and the main frequency becomes the source of the counterfeit goods produced by the bad dealers. They super-high frequency the CPU and modify the identification code of the chip surface. (Rem-ark). In order to prevent such problems, Intel started with the Pentium MMX and added the multiplier lock to the CPU. We can no longer change the multiplier at will, and we can only work hard on the FSB. Overclocking becomes difficult due to the limited frequency setting of the main frequency. For example, the standard overclocking of 300A is 100× 4.5=450, you cannot exceed it to 150× 3=450. Recently, motherboard manufacturers have introduced linear overclocking products, effectively alleviating contradictions. For example, Abit SfotMenu III has 83 choices between 100MHz and 183MHz, that is, 1MHz as the frequency conversion reference.

The most dangerous aspect of the FSB is the frequency of the PCI/AGP. The standard frequency of the PCI is 33MHz, and the standard frequency of the AGP is 66MHz. If the standard frequency is exceeded, the hardware may be damaged. For OverClocker, I offer three of the most secure FSBs: 66, 100, and 133MHz. Their PCI/AGP frequencies are 33/66MHz, and there is absolutely no hardware problem. Recently, some new motherboards have adopted a 2/3 division and a 1/4 division design. As long as both PCI and AGP are running at standard frequencies, it does not matter how much the FSB is over.