Overclocking motherboards on P35, P45, X38 and X48 chipset

[MattyBoy]

This article will explain how to overclock your Core 2 Duo in the particular case of a motherboard with a P35, as the Asus P5K and its derivatives, or Gigabyte P35 (C)-DSR3 and EP35 -DS3P because their potential is amazing: the FSB is 333 Mhz core, it is not uncommon to reach 500 MHz, the limit is around 545 Mhz (it depends on the PC of course).

Those who have a motherboard with P45 chipset can use this article, the P45 chipset is very close to the P35 in overclocking (FSB 333 MHz max core ratio FSB: RAM 1:1 minimum).The fine engraving of P45 to 65nm (instead of the traditional 90nm used on other Intel chipsets) allows it to rise higher in frequency, some having reached 570 MHz FSB!


For X38 and X48 chipsets, this article can also be used, taking into account the specificities of their Bios: For example, a motherboard with 2 Asus chipsets have an additional setting called "FSB Strap to Northbridge". This setting also appears with the latest version of the Asus P5K Bios.

This setting is explained further in the "limit of the FSB" in the "advanced overclocking. In the case of the X48 chipset, the motherboards have a BIOS menu slightly different, for example on an Asus P5E Deluxe, the submenu "jumperfree configuration" in the "advanced" does not exist, it is replaced by the menu "AI Tweaker", which includes setting the FSB and RAM.

Warning: Overclocking a PC may reduce its life, but when we know today that a configuration is obsolete in 5 years ...
In any case, the guarantee will work, because Intel can know if a CPU has been overclocked or not.
The CPU is protected against overheating, but not the individual components of the motherboard including Northbridge and capacitors. For those who are overclocking practice on a permanent basis, it is better to invest in a motherboard with the heat on the Northbridge and capacitors or solid polymers, more resistant to heat. Techarena and the author of this tip can in no way be held liable for any damage caused to your computer.


Note: If you have a PC manufacturer (HP, Dell, Sony, Acer, Fujitsu-Siemens ,...), the BIOS of your motherboard is certainly restrained and will prevent any changes in voltages and frequencies. Would require using software in Windows. I do here that overclocking from bios. I will break this article into 2 parts, one for overclocking simple, accessible to all, and a 2nd party, to take more of your PC.

Here are the following Point to follow :

• Overclocking basics
• Advanced Overclocking

[MattyBoy]

Overclocking basics

The explanation I give here are Core2Duo E6550 and E6850, mounted on an Asus P5KC, and associated with DDR2 800 Mhz C4. This corresponds to many who bought an Asus P5K or Gigabyte P35-DS3R with Core 2 Duo 333 MHz FSB, like a E6750 or E6850. This method can be adapted to an E8400 or E8500, adjusting certain values, such as vCore.


Follow this Steps :

• Reminders on the principle
• Method
• conclusion of the 1st part .

[MattyBoy]

Reminders on the principle

The attempts to overclock the CPU to operate at a frequency higher than that for which it is sold; on an Intel platform, this is to increase the FSB, because this bus determines the CPU frequency, in fact the CPU frequency is calculated as follows:


Frequency = CPU FSB Frequency x CPU coefficient . Or CPU ratio can be lowered but not increased (except for some high-end CPU)

Unfortunately, increasing the FSB without precautionary acts on other components such as RAM or expansion cards, as many elements are calculated from the FSB.

We must therefore determine the frequency of certain elements, and lower than others, so as not to crash the PC.

I propose here to increase the FSB from 333 to 400 Mhz, which corresponds to 20% increase.

[MattyBoy]

Method

To do this, go to the BIOS, at boot the PC, you have to press the DEL key (it depends on the PC, read your manual)

Once in the BIOS for an Asus P5K, you go to the Advanced tab, then select "jumper free configuration", as shown on page 6 of overclocking guide masters

For a Gigabyte P35, see page 5 of this guide, do not forget to press Crtl + F1 to access the advanced menu

You have to select "manual" option for the AI Overclocking .

It must then manually adjust some settings:

• FSB frequency: attach directly to 400 (Mhz)
• PCI E frequency: it should be set to 100 (Mhz)
• DRAM frequency: you must choose DDR2 667 for DDR2 800 Mhz, because moving the FSB of 333 Mhz to 400 Mhz will run the RAM frequency to 667 Mhz to 800 Mhz

Other settings can be "auto", in particular the timings CPU Voltage (vCore) may in this case remain in the car, but it is advisable to be followed by manual safety E6x50 for 1.4V and 1.3V for E8x00

You can then exit the BIOS by saving the changes, reboot and it oh miracle, it works

[MattyBoy]

Conclusion of the 1st part

Well, you earned 20% on the FSB and the CPU frequency, very easily, and you're ready for future CPU at 400 Mhz FSB ...

It is best to check the stability of your PC with specialized software, such as CPU Stress Multithread or OCCCT orthos or PC2004

Of course, we must verify the frequencies obtained with CPU-z

For security, I suggest you still monitoring the temperatures of different components, with SpeedFan or Everest, for example NorthBridge temperature is rarely given, unfortunately, we can control about putting his finger on the radiator Northbridge: if you can keep your finger over the temperature is below 50 ? C

If the Northbridge heat a little, you can add a small fan to 4 cm, or put a side fan, if possible on your box, as shown in the "Advanced".

RAM remaining at face value, there are no special precautions to take, if we choose quality RAM with DDR2 800 Mhz, they incorporated a radiator, and the breath of the CPU fan is sufficient to cool

If you have an E 6850, it is not the 3.6 Ghz without increasing the vCore, and this basic overclocking, it's better down the coef CPU 8 in the Bios

For example, with my E6550 (FSB 333 Mhz, 2.33 Ghz Freq) and my Asus P5KC, I get 400 MHz FSB frequency and CPU 2.8 Ghz without any problem
With the E6850 (FSB 333 Mhz, 3.0 Ghz Freq) P5KC and still, I get FSB 400 MHz and 3.2 GHz CPU Frequency (CPU coef = 8)

vCore the car passes the voltage to 1.4 V, there was no heating in my E6550 does not exceed 40 ? C with the original Intel ventirad in idle, and does not exceed 50 ? C stress

With the E6850, I rule vCore = 1.4V (1.36V measured by CPU-z), it does not exceed 45 ? C idle and 55 ? C in the stress with Intel RadBox, fan out (Q-Fan disabled).

[MattyBoy]

Advanced Overclocking

Here, it is for those who have already completed the 1st part and want to go further

We search separately for these 3 elements: the FSB, the RAM, the CPU ,,,you must cool more effectively the various components: the Northbridge, RAM and CPU, and motherboard, especially if you increase tensions: V Northbridge, RAM and vCore V

Attention! A modern CPU is normally well protected against overheating (cut it in case of excess heat), but the Northbridge and other components of the motherboard do not have that protection!
In addition, excessive tension on the CPU (vCore "or" CPU Voltage ") on the chipset (NB Core Voltage" or "NorthBridge Voltage Control") or the RAM ( "VRAM") can be destructive!


It must monitor during the process of overclocking the temperatures, the frequency and vCore, eg Ultimate Everest and CPU-z and add fans if necessary

Keep in mind that the main danger for your hardware at overclocking does not normally frequent excessive, but an excess of tension, generating excessive heat.

The following Point to refer :

• limit of the FSB
• RAM limit
• CPU limit
• Conclusion of the 2nd part

[MattyBoy]

Limit of the FSB

To check the limit of the FSB of your motherboard, it is better to have the DDR2 1066 Mhz .

In fact, DDR2 800 Mhz 880-900 Mhz reached at 2.0V, and is just over 1000 MHz at 2.4 V CAS 5 (test results of the magazine PC assembly Jan-2008 on February 4 kits DDR2 800 and 5 DDR2 kits 1066) .

DDR2 1066 running smoothly to 1066 Mhz at 2.0V in 5 CASES, it is easier to find the limit of the FSB with the memory.

As in Part 1, you go to the BIOS: for an Asus P5K, you go to the Advanced tab, then select "jumper free configuration", as shown on page 6 of overclocking guide masters. For a Gigabyte P35, see page 5 of the guide, by enabling the advanced bios menu by pressing Crtl + F1

You have to select "manual" for the AI Overclocking option, as in the 1st part

Then manually adjust some settings.

• FSB frequency: go directly 400 (Mhz), then at each reboot, it rises to 20 MHz and 10 MHz from 450 MHz PCI E
• frequency: it should be set to 100 (Mhz) DRAM
• frequency: you must choose to DDR2 667 to DDR2 1066 Mhz, because moving the FSB of 333 Mhz to 500 Mhz will run the RAM frequency to 667 Mhz to 1000 Mhz
• CPU Ratio: 6 to fix
• CPU Voltage: set at the start E6x50 for 1.4V and 1.3V for a 8x00 E, do not leave it in auto, it could rise to excessive values

In this way, all PC crashes can be attributed to the FSB, because with a 500 Mhz FSB, DDR2 1066 does not exceed 1000 Mhz and the CPU will be 6 x 3 = 500 GHz, it must smoothly, you have an E 6550, 6750 or 6850

All optional features must be disabled to avoid instabilities associated with reductions in voltage / frequency systems for energy savings: Spread Spectrum, Vanderpool, EIST, CPU TM function, as explained ... masters control energy EIST, in some cases may be left in use to reduce the consolidation of CPU usage, but it is better to disable it to validate its performance in CPU-z

In the case of motherboards with X38 and X48 chipset, as well as the latest BIOS Asus P5K, a further adjustment Bios appears: FSB Strap to Northbridge.

This coefficient allows the chipset to generate the FSB from an internal clock. Plus the strap chosen, the lower the internal clock must be high, which improves latency. But you can not get too low either: it is generally advisable to be somewhat below the nominal strap.

It is against necessary to cool the Northbridge, as it tends to be heated, for example by adding a small fan on the radiator:Motherboards with X38 and X48 chipset will not need this little fan, the cooling system is more developed.



If your camera has a slot for an optional side fan, install one, it is the best solution to properly cool the various components of the motherboard. Once the limit of the FSB found, you can go to the next step: the limit of RAM

[MattyBoy]

RAM limit

You can follow the method described by Overclocking masters, and it saves time thanks to information from the magazine PC assembly:

We already know that the limit of DDR2 800 Mhz is about 880 MHz at 2.0V, and from 1000 Mhz to 2.4 V, but that this tension, the strips much heat, with the result of random crashes and durability reduced.



You can use a ramp ventilos to cool the RAM, like in this picture:

If you have DDR2 1066, it reached about 1100 Mhz to 2.0 V, and this tension nipples little heat.

The overclocking of the RAM is less spectacular than the FSB, because it earns at best 20% against 50% for the FSB.

[MattyBoy]

CPU limit

To find the limit of the CPU, it leaves a nominal FSB CPU with a nominal factor (7 for E 6550, 8 for 6750 E and 9 for E 6850)

It sets the RAM to 667 and increase the FSB until instability

Except perhaps for the E6550, which has a low coefficient, the limit of the CPU must arrive before the FSB

Once the CPU limit is reached, we can try to go higher by increasing the CPU voltage to 0.01V in steps, and again, until it is unstable or gives errors such as OCCT

Caution: Under no circumstances exceed the voltage shown in the table on page 6 of the guide Overclex. CPU Voltage (vCore) may be important too destructive!

Should be replaced by the Intel ventirad more efficient if we want to exceed 1.45V vCore a E6x50, Scythe Ninja 2 or OCZ Vendetta 2 for example, on pain of having errors in software testing as OCCT or worst set CPU thermal safety.

I invite you to read comparative ventirads yours to choose, as here for example.

The ventirads blowing to cool the motherboard as the Northbridge and RAM:

[MattyBoy]

Conclusion of the 2nd part

The final adjustment will be an optimization between the 3 limits of the FSB, the RAM and CPU

It saves time because it already gives an idea of what we can get its platform, without making adjustments rather tedious and error.

We see how you can achieve frequencies of 500 Mhz FSB with P35, a CPU frequency of 3.8 GHz for the E 6750 and 4 GHz for the 6850 E! but beware, this is obtained by adjusting the different voltages vCore, V Northbridge, FSB termination V and V RAM must verify the frequencies obtained with CPU-z and validation!

In my case with my E6550 and my Asus P5KC, I got:

With the FSB at 450 Mhz, it provides 900 MHz with 2.2V on my nipples Corsair they moderately hot (you can keep control of their problem without radiator) With the FSB to 460 Mhz, RAM running at 920 Mhz, which is its maximum 2.2 V With the FSB to 470 Mhz, RAM running at 940 Mhz, but there are errors PC becomes unstable if I increase the VRAM voltage beyond 2.2V, so it is my RAM, which limits


It is therefore stable: FSB 460 Mhz, 920 Mhz RAM (RAM Ratio: 1:1 FSB) and CPU 3.22 Ghz Frequency:
http://valid.x86-secret.com/show_oc.php?id=361350

Personally, I did not change the V Northbridge (NB Core Voltage), which has always been in "auto" . To not push the hardware too, I reduced to FSB = 450Mhz, Freq = 900Mhz RAM and CPU Freq = 3.15Ghz

This is better than a E6850 at the lowest cost, but with probably a life somewhat reduced ,,the vCore manually is 1.45 V, the heating is acceptable, my E6550 does not exceed 40 ? C in idle and 55 ? C with the stress ventirad original Intel (base Aillet Copper and Aluminum), but I replaced the original thermal pad by the Artic Silver 5 and the fan is an Intel model 0.6A (others are 0.2A or 0.4A)

With my E6850, I limit myself wisely in a 20% overclock, which means FSB = 400 MHz and CPU Freq = 3.6GHz, which is not bad, because more powerful than the E8600 at its nominal frequency (3.33 ghz) the vCore is set manually is 1.4V (measured at 1.35V in the BIOS), I preferred to replace the Intel ventirad by a more efficient .

I took a ventirad blowing towards the motherboard to mount ventilos in the side door . In order to better cool the components of the motherboard including Northbridge, I added 2 ventilos 120 mm on the left side of the PC, controlled by the speed in Bios: temperatures remain very reasonable

Here inside my PC with the E6550, we see the Intel ventirad top, and blue fan on the Northbridge below, and we see the radiator black vertical bar DDR2 800 Mhz, right, just before the cables Feed