OCing P4 2.4C

[Firochromis]

Hi fellow O/Cers,

I'm new in the community so hope to learn much from you :)

I want to oc the system in my sig. Asus mobo gives an automatic oc option and I choose %30. It gives a core speed of 3124 MHz. When I ran the prime 95 test it gave an error while using 1280K FFT length. After that I started torture test and system doing fine till 3 hours ( definitely I' ll continue the test on).

My question is, isnt' that values are too low? Although my memories are cheapy Kingstons (173.6MHz, 3-4-4-8 during tests) I hoped a much more high core speed..

Any bits of information will be appreciated..

Regards

[Blunt]

nah set your overclock to manual and just for starteers set the fsb to 250 memory to 320mhz and lock your pci/agp to 33/66


WELCOME TO THE FORUMS

[Firochromis]

Thank you blunt. I changed my settings. But what I can I do if I want core speed around 3.4Ghz?

Regards

[black_dog]

Like Blunt said, lock your agp/pci at 33/66mhz

PC 3200 ram should be able to do 400mhz DDR (200mhz fsb) albiet with lax timmings.

To reach 3.4 ghz you will need a front side bus of 283.33 mhz

Set memory speed to 320mhz for the 5:4 divider
This will yield a memory speed of 250mhz and a cpu speed of 3000

To go higher you will need to set the memory speed at 266mhz for the 3:2 divider. This will yield a memory speed of 303mhz and a cpu speed of 3636 mhz.

You should start by setting your memory to the 266mhz option and then crank up the cpu fsb to determine what is the maximum fsb of the CPU. One you find this spot you can start lowering the memory timmings for better bandwidth.

You will have to experiment with different cpu fsb and memory speeds to ascertain the best performance (benchmarking). Please note that most 2.4c's overclock to around 3.1 to 3.3 ghz. Your PC 3200 ram may limit your system performance since with a 5:4 divider will yield 3000mhz. Any overclock over this and you will have to use the 3:2 divider. At 3.2ghz with the 3:2 divider, your memory will be at 176mhz (352 DDR). That is lower than 200mhz (400 DDR) that your ram is capable of.

To sum it up, try setting the ram at 266mhz (3:2) and see how far you can push your cpu. The max speed of your cpu will determine what you can run your memory at.

Your two options are:
1.) 320mhz memory speed (5:4) + 3000mhz cpu speed and timmings set accordingly.
2.) 266mhz memory speed (3:2) + 3000-3636mhz cpu speed and tighter memory timmings than spec since you will most likely be running below 200mhz (400 DDR)

Let us know how it turns out.

[Firochromis]

Hi,

How can we change between 5:4 and 3:2 dividers. I can not see something like that. As I said befero I'm a newbie :cry:

[Firochromis]

Well, I think I guess how can we chane them. We just select the memory speed and dividers are set accordingly. For 320MHz the divider is (5:4), for 266MHz the divider is (3:2) and for 400MHz the divider is (1:1)

If all these are true what are the difference between them??

[black_dog]

CPU front side bus x memory ratio/divider = overall memory speed.


Default 2.4c 200mhz fsb x 400 mhz DDR (1:1) = 200mhz (400 DDR) memory.

Default 2.4c 200mhz fsb x 320 mhz DDR (5:4) = 160mhz (320 DDR) memory.

Default 2.4c 200mhz fsb x 266 mhz DDR (3:2) = 133mhz (320 DDR) memory.

These ratios allow you to use different speed memory with different Intel cpu to gain the most effective bandwidth available. THey also help us overclock the cpu by allowing us to conrtol the speed of the memory.

[Firochromis]

Hi,

I have been trying for two days but results aren' t perfect. In fact even not good :bang head

First as my bios version was old enough I updated it and keep trying on v.1011.

With FSB 250, 5:4 divider and default voltage the system is stable (24+ hours running Prime95)

When I try 3:2 the results are discouraging. With default voltage and 3:2 divider I tried 275, 267 and 259. Windows started only in the last trial but Prime95 gave an immediate error. In all this trials I did not change the RAM timings. Next I tried a little bit voltage increase to 1.6 to see the differences. But the result was the same.

3.0GHz with default voltage (and considering cheapy memory chips) is not bad but here and there people doing 3.4GHz w/default voltage makes me continue on.

Any advices?