Ok go to CPU/Processors and Overclocking section and ask how to overclock 2.4 on Asus P4P800. Also you can use the search button and type overclocking P4 C or something along those lines and it will give you a lot of threads. I'll try to cover the basics.
1. 2400mhz p4 C is in your possession meaning it has a multiplier 12 and runs at Front Side Bus (FSB) speed of 200. Since P4 is 'quad-pumped' in reality it runs at 200x4 or 800FSB. Thats how you get the designation 2.4ghz 800FSB CPU.
2. Theoretically in the best possible scenario, especially at stock speeds you should run the memory and CPU synchronously or at identical speeds. For instance if your Ram is rated at PC3200 (to figure out its true speed divide by 8 => 3200/8 = 400mhz in dual-channel or 200mhz basic speed which matches the 200FSB of the cpu) Therefore, this is called 1:1 ratio when your CPU:RAM ratio = 200FSB (800Effective): 200mhz (400mhz/PC3200 memory effective)
3. To overclock, I suggested that you use ratios, because your ram is already at a disadvantage of running at 166mhz (or 333 effective). The idea is for you to raise the FSB of the CPU from 200 to as high as you can go for the best speed, and keep the ram speed as fast as possible while having the lowest possible latency timings (ie. 2-3-3-6 or lower)
So here is an example. Let's say you have 2400 (12x200) @ 250FSB => 12x250 = 3000mhz
I am assuming your motherboard is set as CPU:RAM in the BIOS not vice versa, if it is just use math logic to figure it out.
In this case if you wanted to keep 1:1 ratio, you would need 250mhz memory (or PC4000, 4000/8 = 500dual channel)
Since your memory does not run at 250 this speed is out of the question.
With 5:4 ratio you would then have 250:x => 5:4 so what does x have to be? 250/x = 5/4 = 250x4/5 = 200mhz or need 400mhz dual channel ram which you dont have either.
Lets go to 3:2 ratio 250:x = 3:2 or similarly you'll get CPU:RAM 250:166 which is perfect for you since you have PC2700 or 333mhz dual channel ram.
4. Now to overclocking in the BIOS:
- Relax memory timings of your ram to 2.5-4-4-7 if you can or higher leave it at stock voltage.
- since we don't want to hit a wall with your ram set teh CPU:RAM ratio at 3:2 right away.
- Enable PCI/AGP lock fix => since it's set at 33/66, when you overclock FSB then everything gets overclocked and you do not want to send too much to your other components like hard drive and videocard as they are very sensitive to thse changes and you can damage them so enable it at all times especially if you are new to O/C
- Then go to the CPU FSB and start raising it by 10 so from 200 to 210 then 220 and so until the computer cannot boot anymore. This will tell you how high you can go without increasing the CPU voltage on default voltage speeds. Your goal is to reach 3.0ghz as that is the maximum your ram will allow without overclocking it or buying faster ram.
- If you cput won't boot, and you are worried about long-term survival raise the voltage to no more than 1.6-1.65 VCore from 1.48-1.55 default. The general rule of thumb is to be safe to not raise the voltage higher than 10% from the default voltage. I am sure asus has some program like ASUS PC probe that helps you read the voltages and so on.
Also you can check these readings in the BIOS.
Once the CPU boots in happily you should try to adjust the ram to as tight timings as possible, if you ram supports voltage up to 2.8 or higher, set it at the voltage that allows for stable tight timings. So if your ram is rated for 2.8 and at 2.8 you can get 2-2-2-6 timings and with 2.7 you cannot get that then set it at 2.8. If increasing the voltage does not affect timings, then leave at the lowest possible setting since what's the use of upping the voltage if it has no effect for no reason?
Sometimes increasing the AGP voltage from 1.5 to 1.6 helps to gain stability as videocards can be affected by overclocking. I am not sure why, but often even with PCI/AGP lock enabled, stability of them can be compromised.
Also make sure your CPU does not run faster then 60-65*C on a hot day. I am sure with a stock cooler you can do the above procedure if you are not pushing above 3.0ghz. You can look into other coolers buy asking in this forum. I can recommend Zalman CNPS7000A-ALCU or 7000-ALCU as it is quiet and cools very well and you dont have to worry about installing a fan if that's not your thing. Thermalright has excellent coolers as well.
Your motherboard might have other performance featues like Turbo mode so you might want to tweak around to see at what fastest of those settings the overclock becomes stable.
To test for stability use these:
Tests CPU/RAM/Motherboard stability
Prime 95
and run it for 24 hours make sure you do not get errors, if you do your system stability is possibly compromised (thats when the increase in voltage of the cpu/ram comes in)
Memtest86 or MemTest or
Windows Memory Test to check for memory stability. You have to downlod these to a floppy and boot up the computer and on start up put floppy as the 1st bootable device it will do the rest. Test the memory for 1 hour if you want. Usually the errors appear in the first 10 min.
To check for CPU/RAM (FSB) speed, etc use these:
WCPUID3.1a (check under Download section)
CPU-Z version 1.21
And for general information and some benchmarking, to see voltage, cpu temperature, etc.
SiSoftware Sandra 2004 Download
Good luck, and remember there are many people who can answer your question, especially those with the same motherboard and cpu as you. You have the option to post on the Asus forum as well to get even more suggestions and responses. Good luck.
