Overclocking the P4 For not-so-dummies by Farhan Mohamed Ali
Page 1
Intro

Page 2
Factors affecting overclock & Stability Testing

Page 3
Changing bios settings and overclocking

Page 4
Updates and  Final Words

 

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TWEAKING BIOS SETTINGS AND OVERCLOCKING!

For a complete guide on bios settings and their functions, please visit this page

I am assuming that you want to find out the maximum overclock of your CPU 1st and therefore I will not emphasize on the RAM performance until later. And please remember, to get the maximum overclock, you must be willing to spend a LOT of time tweaking your system and testing for stability.

Now that you have all the equipment set up, turn on your pc and get into your BIOS setup. This is usually done by pressing the "del" or "F1" key on startup. For this guide I will be using an ABIT IS7-E mainboard, so keep in mind that BIOS setup screens may slightly vary according to mainboard model and manufacturer. Nevertheless, the basic BIOS settings should be similar no matter what mainboard you use.

Main BIOS setup screen:

Click on thumbnail to view full picture

From the main BIOS screen, select the option where you can adjust the processor voltage, multipliers etc. For ABIT boards, this will be the Softmenu Setup (highlighted above).

 

Softmenu Setup:

Click on thumbnail to view full picture

Now change the CPU operating speed option to User Defined or something similar. Notice that the text below this option can now be selected.

For ASUS mainboard users, set the AI Overclock Tuner to Manual.

For more information on RAM timings and setting FSB:RAM ratio (ABIT, ASUS, DFI), read my RAM tweaking guide. FSB:RAM ratios are on page 3

Now, this is what you must do, step by step:

  1. Set the AGP Ratio to fixed.
     
  2. Set the Fixed AGP/PCI Frequency to 66/33MHz.
     
  3. Set the CPU Power Supply option to User Defined.
     
  4. Increase the DDR SDRAM voltage to at least 2.70v. This is just a precaution to make sure that the RAM is stable. Such a small voltage increase will not hurt your RAM. Those running DDR500+ RAM should increase it to at least 2.80v else your RAM might not work properly.
     
  5. Also, set the AGP Voltage option to 1.6v. I have noticed that this is the most stable setting for my system. This may or may not help you, so AFTER you overclock to the limit, just test out the different settings from 1.50v to 1.65v to see which one gives you the most stable setting.
     
  6. Set the N/B Strap CPU As to By CPU.
     
  7. If you are running DDR400 RAM Change the DRAM Ratio option to 5:4 (DDR333 on ASUS boards). This means that your RAM will run at 4/5 or 80% of the FSB speed. This is to make sure that your RAM is not limiting the CPU overclock. Those who are running DDR500+ RAM can leave this setting at default or by SPD or 1:1(DDR400 on ASUS boards).
     
  8. For more information on RAM timings and setting FSB:RAM ratio (ABIT, ASUS, DFI), read my RAM tweaking guide. FSB:RAM ratios are on page 3.
     

Now you are all set to overclock. The default FSB (sometimes called External Clock in the BIOS) for the P4C chips is 200MHz. Remember that the final clockspeed of your CPU is the result of the FSB speed*CPU multiplier. For the P4 2.4C, the multiplier is 12, for 2.6C, it is 13, and so on... I'm sure you get the trend... :)

Now, lets begin the fun part! Overclocking!

Remember that if your computer will not boot after you save the BIOS settings and exit, just turn it off, wait at least 30 seconds, and hold the INSERT key when you turn it on again. Also, please remember to keep the CPU temperature below 65șC. This is to make sure your system does not overheat and the P4's overheating protection will kick in and slow your system down.

Lets begin overclocking :

  1. Increase the Ext. Clock by 10MHz. The default is 200/66/33, so after the increment it should read 210/66/33.
     
  2. Save the settings and exit the BIOS.
     
  3. Your computer should boot up flawlessly. Now get into windows and run the Prime95 torture test for at 20-30 minutes. (The higher you increase the speed, the longer you should run Prime95 to ensure that your system is stable).
     
  4. Repeat steps 1, 2, and 3 until you get errors in the Prime95 torture test. This means the system is somewhat unstable. Now you have 2 options to choose from:
    1. Decrease the FSB (Ext Clock) a by 5 MHz then run Prime95 torture test for a few hours (I recommend 3 to 4 hours) to make sure it is stable. If it is still not stable, you can either reduce it some more or refer to option (b) below
    2. Increase the CPU Core voltage by one step (0.025v). This is usually the better option as long as the voltage is still below 1.65v. DO NOT increase the voltage beyond 1.70v as this might kill your CPU. Run Prime95 torture test for a few hours (I recommend 3 to 4 hours) to make sure your system is stable. If still unstable, you can increase it some more, or if it is already high (1.65v and above), you should refer to option (a) above.
       
  5. If you increase the voltage a few times and the system is still unstable, you might have reached the limit of your processor. You should refer to step 4.(a) and reduce the FSB by 5 MHz before torture testing again.
     
  6. Do not forget about the RAM!
    1. For those running DDR400 RAM, remember to change the DRAM Ratio to 3:2 once your FSB exceeds around 250 MHz.
    2. For those running DDR500+ RAM, make sure that the RAM timings are set to 3-8-4-4 in the Advanced Chipset Features screen (refer to this picture). Once your FSB exceeds 250 MHz, change the DRAM Ratio to 5:4.
    3. The above is to make sure your RAM stays within spec and will not limit the CPU overclock.
       
  7. Once you have found the sweet spot between FSB speed and core voltage, run Prime95 torture test for at least 5 hours just to make sure it is completely stable. If it is not stable after a few hours, reduce the FSB by 5 MHz and try again. It should work fine now. Run Prime95 again (seeing the trend here?) After that play all your favorite games and run all your favorite benchmarks to stress test. If still a little bit unstable i.e the games/benchmarks crash after a few hours of running, lower the FSB some 2-3 MHz. This should fix the problem. Yes, you guessed it. Prime95 again.... Repeat until completely stable for at least 5 hours.

For more info about RAM tweaking, go to this article.

Congratulations! You should now have a stable, overclocked system!

Next Page - Final Words

 

 

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Copyright© 2004 by Farhan Mohamed Ali