Chapter 18: Examples and Analysis of PC Overclocking

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Overview

The implementation of the overclocking modes for PC components improves overall system performance. If several simple recommendations are observed, implementation of moderate overclocking modes for desktop PCs does not noticeably reduce stability and reliability. Evaluation of the performance growth achieved for various hardware configurations is possible by analyzing the results achieved during the experiments described in detail in this chapter.

Before reproducing the experiments described in this chapter, it is necessary to remind you once again that you must be very careful when using these over-clocking methods. You should constantly bear in mind that the overclocking operations might produce irreversible results. Your processor might end its life in smoke, your video adapter or hard disk may fail, and so on. In other words, when trying to achieve the highest possible results, you are not protected against the loss of a usable computer.

The plan for increasing the performance of your system must be comprehensive. The following advice emphasizes several aspects directly related to the implementation of the overclocking modes:

1. Perform detailed physical diagnostics of the system and carefully read the documentation. This will help you understand the possible ways of optimizing and overclocking your system. The implementation of overclocking modes sometimes requires you to open the system unit case. This allows you to identify the system components correctly. Besides this, it will help you make sure that all components are present, that there are no loose or unneeded wires, etc.

   The following situation is an illustrative example: When inspecting the system unit components, it was detected that the fan connection to the motherboard was insecure. This could have caused the fan to stop, which would cause CPU overheating and failure. Besides this, it was necessary to correct the cable connection between the motherboard and hard disk. All loose cables and wires were carefully bound together. This improved the ventilation of all components within the system unit case.

2. Carefully test all functional capabilities of the computer to be overclocked. Make sure that all components operate normally in the nominal mode. To perform this check, it is recommended that you employ popular testing software, by doing the following:

   • Start popular tests (Winstone, WinBench, CheckIt, etc.) and run them several times

   • Try to work in popular applications (Word/Excel, CorelDraw, Photoshop, Xing, Winamp, etc.)

   • Perform sequential checks of your computer using popular games (Doom, Descent, Quake, etc.)

   If you are conducting tests, record the results obtained. (At least, write the results and preserve them as a hard copy.) You can proceed only after you make sure the computer is usable and its operation is stable.

3. Using either BIOS Setup or the appropriate jumpers on the motherboard, set the desired overclocking mode. Proceed step by step. For example, it makes sense to increase the system-bus frequency slightly (from 133 MHz to 145 MHz or in smaller increments, if they are supported by the motherboard.) It is not recommended to jump several steps (from 100 MHz to 150 MHz or from 133 MHz to 166 MHz). The best approach is to do everything gradually (remembering to record every step). If you keep track of each step that you have taken, then, if anything goes wrong, you'll be able to perform a smooth rollback to the previous mode.

4. Remember that the entire system, and especially the processor, requires adequate cooling. It often is necessary to install a massive heatsink and a powerful cooler on the processor, the video adapter, and possibly on other hardware components.

5. Repeat the testing described in Step 1, but as long as possible and under the hardest conditions. Some recommendations on testing computer systems were provided in Chapter 7. If you discover any problems or instability, find the reason and take the steps necessary to eliminate the problem. Sometimes, you'll have to return to the previous step or even abandon the idea of overclocking this particular computer. If the system is usable and stable, proceed to the next step.

   Suppose that not all tests were passed normally: There was a failure at the second stage of the testing process, related to playing video clips. When performing this test, the system hung up after 40 minutes of operation. This led to a conclusion that the system was unstable. In this situation, you can consider returning to the previous mode. However, there are other approaches to the problem: You could try to improve the cooling system of the processor and/or other components, replace the unstable component, and so on. After analyzing the situation and carefully investigating the operation of all hardware components of this particular system, the conclusion was drawn that the video adapter was causing the problem. This component became unstable because, in the course of overclocking, the Accelerated Graphics Port (AGP) bus frequency increased to 83 MHz. As a result, the heat emission of the graphical core grew accordingly, and the adapter became overheated. Replacing the cooler installed on the video adapter with a more powerful one returned stability to the system and enabled it to operate reliably in this particular overclocking mode.

6. Change the settings in BIOS Setup. This can be accomplished before, after, or even instead of overclocking. This usually relates to parameters of memory operation. Sometimes it is possible to significantly increase memory subsystem performance by changing several parameters in BIOS Setup. Extreme caution still is required, as well as testing.

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