Overclock of p4p800f!

Discussion in 'Overclocking, Benching & Modding' started by jocker95, Dec 6, 2012.

  1. jocker95

    jocker95 New Member

    Dec 6, 2012
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    Hi all, I have a p4p800f of asus, and I would do a overclock of the processor that is a intel celeron 2 ghz. How can I do it ?? because in bios you cannot change the speed of the processor! please help me ;) At this moment the computer is very slow and , I think that depends on the processor!
  2. CDsDontBurn

    CDsDontBurn AMD & Petrol Heads Mod

    May 24, 2003
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    You change the FSB of the CPU, not the CPU speed itself. Then, you need to make sure you have RAM that is fast. A 2Ghz Intel p4 is 533Mhz IIRC, so if you have any DDR400 RAM, you'd be doing just great as a 533Mhz FSB will only require DDR333 to run at a 1:1 ratio which is what you want anyways.

    Basiclaly, what you want to do is increase the CPU's FSB by, say, 10Mhz at a time from 533Mhz and increase the RAM as well accordingly to maintain the 1:1 ratio. As you increase the FSB, you'll also be increasing the speed of the CPU.

    The way it works is like this:

    Your CPU has a multiplier of Y and a "base" FSB of Z. If your CPU is indeed has a 533Mhz FSB at 2Ghz, then your multiplier should be 15 and your "base" FSB is 133Mhz. So, in your case 15 x 133 = 1995Mhz (2Ghz rounded up).

    As for FSB, the reason why I put "base" in quotes is because the FSB is "quad-pumped" or multiplied by 4. So, your CPU in reality has a "true" FSB of 533Mhz. Why? Because 133 x 4 = 533.

    Then, with RAM you have to remember that the "true" speed is in reality double the actual speed. So, DDR333 is 333Mhz but the "true" speed is actually 166Mhz. Why? Because 166 x 2 = 333Mhz. DDR400 is the same thing. But instead of 166Mhz, it's 200Mhz because 200 x 2 = 400Mhz.

    So, if you have DDR400 you can adjust both the CPU FSB from 133 and drop the RAM's speed from 200 down to 133 in order to run a 1:1 ratio. You would then need to increase both the RAM speed and CPU's FSB up 10Mhz at a time and you'd be able to maintain the 1:1 ratio. Save changes and a reboot would be needed for these settings to take effect. If your system is stable (you would need to benchmark your system or run a stability test of some sort) then you can go back and adjust both the RAM and FSB a few more Mhz and try it all over again. Once your system becomes unstable, then you would need to increase the voltage to the CPU. Your system BIOS would need to support CPU voltage increase for that to happen though. If it doesn't, or voltage adjustments are limited, then you won't be able to do much more in terms of overclocking.

    But, that's basically the run-down on OCing your older system. :)

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