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Old 02-09-2010
Join Date: Sep 2005
Posts: 1,306
Official Phenom and AM2/AM2+ Overclocking

AMD has finally released the overclocking tool dedicated to its Spider platform last November presented. Called OverDrive utility that allows you to influence the frequency of each core Phenom processors. It allows you to edit the settings memory, display system temperatures and perform various benchmarks and varied, and stability tests. All is done in real time, without restarting the computer. The only problem, this utility is intended only to owners of cards accompanied AMD 790FX processors Phenom.

AMD Phenom (K10)

I am providing you reference of my processor AMD Phenom (K10). Look below for further detail on overclocking for AM2 Socket.

When AMD Phenom or Athlon II there are five different types of stroke:
  • Reference clock
  • Processor clock
  • North Bridge clock (short NB-clock)
  • HyperTransport link (in short: HT link)
  • Memory Clock

The reference clock is with the Phenom just like the K8 in the normal state at 200 MHz and using the multiplier arises from the real processor speed. The North Bridge clock and the HT-Link will also be calculated by multiplying the reference clock. The memory clock is calculated as opposed to the K8 means of a ratio, also from the reference clock.

The North Bridge clock affects the performance of the system, as operated, for example, the L3 cache with this bar. Higher NB-stroke therefore means higher L3-stroke. The effect of a higher NB-bar on the performance of the processor depends greatly on the used application. Memory-intensive applications (e.g., pack / unpack it with WinRAR, some games benefit) is relatively strong, other applications (such as ray tracing with POV-Ray and Cinebench rendering) to benefit almost not at all. An overview of the performance change in a modified North Bridge clock receives the kind users in the review of the first Socket AM3 processors.

Take for example the current practice of AMD flagship Phenom X4 II 955 BE. This is operated with a clock speed of 3.2 GHz and a multiplier of 16. The clock rates are as follows:
  1. Reference Clock 200 MHz
  2. Processor clock = 200 x 16 = 3200 MHz
  3. North Bridge clock = 200 x 10 = 2,000 MHz
  4. HT link = 200 x 10 = 2,000 MHz
  5. Memory clock or DDR2-1066 DDR3-1333

Run CPUz to get more information on your processor. The North Bridge clock is calculated from 200 MHz reference clock with multi-10th The HT-Link is also calculated by Multi 10x200th.

The memory clock is calculated based on the reference clock with these conditions:
  • DDR2-400: 1:1 (200 MHz reference clock, 200 MHz real memory clock)
  • DDR2-533: 3:4 (200 MHz reference clock, 266 MHz real memory clock)
  • DDR2-667: 3:5 (200 MHz reference clock, 333 MHz real memory clock)
  • DDR2-800: 1:2 (200 MHz reference clock, 400 MHz real memory clock)
  • DDR2-1066: 3:8 (200 MHz reference clock, 533 MHz real memory clock)

With the introduction of the Socket AM3 with DDR3 support were added following memory clock ratios:
  • DDR3-800: 1:2 (200 MHz reference clock, 400 MHz real memory clock)
  • DDR3-1066: 3:8 (200 MHz reference clock, 533 MHz real memory clock)
  • DDR3-1333: 3:10 (200 MHz reference clock, 666 MHz real memory clock)
  • DDR3-1600: 1:4 (200 MHz reference clock, 800 MHz real memory clock)

There are some restrictions exist with respect to the memory assembly. DDR2-1066, for example, is only supported when used per channel bars. If used with four bars, DDR2-1066 is not officially scheduled, and is therefore - as so often when overclocking - to pure luck. The same is true with DDR3 RAM. Here, too, DDR3-1333 is no longer officially supported, instead, will use DDR3-1066. DDR3-1600 is offered in the BIOS but, while many boards, but is seen as a pure overclocking profile and is supported by AMD in any constellation.

While the Athlon 64 (AM2) because of the complicated calculation, not every memory clock was possible for each processor speed and memory had to be so partially operated far below the specification (especially users of processors with odd or half multipliers can tell you a little song), has this picture changed dramatically. Because the memory clock is derived from the reference clock, each processor cycle and the full memory clock is possible. The processor multiplier plays no role.

As you see, is the direct influence of the real clock speed is not possible. It only changed the fundamentals of the corresponding clock speeds, by changing either the reference clock multiplier, or the equivalent, or the ratio.
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Old 02-09-2010
Join Date: Sep 2005
Posts: 1,306
Re: Official Phenom and AM2/AM2+ Overclocking

Phenom platform

AMD Phenom or Athlon II are backwards compatible. This means that the processors can be used in older motherboards. An AMD Phenom X3 8750 Socket AM2 + for example, can also be used in an AM2 motherboard. When running an AMD Phenom in an AM2 motherboard is important to note that the maximum HT link depends on the chipset and not a K10. This means that once again the rule applies as with the K8 to keep the HT link as possible in the range of 1000 MHz.

Condition for the operation of a K10 in a purebred AM2 motherboard is the support of the processor by the BIOS. Sorry, no widespread support for the K10 is given, this will however change in the near future. If you want to know if his AM2 board is Phenom ready, take a look at our collective forum thread throw. There, the sheets of the current support can be found on many motherboards.

The introduction of the Phenom I along with socket AM2 + motherboards in November 2007, exclusively with AMD chipsets of the 700 family (790FX, 770, 790GX later) is available. In May 2008, NVIDIA nForce 780a SLI followed with the 8200 / 8300 and the. Since then, on the chip sector did little. AMD's chipset portfolio is unchanged and was only added at NVIDIA nForce 980a SLI. This is however merely a 780a SLI, which is optimized for use on an AM3 motherboard.

Socket AM2 + / Socket AM3

AMD's Socket AM2 and AM2 + are performed physically identical. Both use Socket 940 pins with identical arrangement, so Phenom processor (AM2 + fit) in AM2 motherboards and vice versa. For the correct function of the aforementioned BIOS update is necessary. With the introduction of the Socket AM3 in February 2009 was added to support DDR3. This requires the use of a DDR3 memory controller on-DIE necessary. do not offer as AM2 and AM2 + CPUs that controller, they had access be denied the AM3 socket physically. AMD has implemented this by using a different pin layout. Simultaneously, the pin count of the AM3 processors has been reduced to 938th.

AM3 processors have, however, a combination controller and can therefore deal with both DDR2 and DDR3. The pin-layout of the AM3 processors allows it to use the CPUs on socket AM2 + DDR2 together. Requirement here for suitable BIOS is the motherboard manufacturer.

AMD Phenom X4 9750 Agena‎

The first Phenom processors have all been manufactured in 65 nm feature size. Unfortunately, these processors have relatively high power consumption at a comparably low clock (when introducing the fastest model was clocked at 2.3 GHz). In addition, the OC potential was often very low. In addition came the famous and infamous TLB bug in the B2 stepping , which partly led to severe performance penalty.

Suppose we use an AMD Phenom 9600 in connection with DDR2-800 and change the reference clock from 200 to 220 MHz. For the HT-Link Multi 5 we share as given. This results in the following clock speeds:
  1. Processor clock = 220 x 11.5 = 2530 MHz
  2. NB-stroke = 220 x 9 = 1980 MHz
  3. Memory Frequency = 220 / 1 x 2 = 440 MHz and DDR2-880
  4. HT link = 220 x 5 = 1100 MHz

The overclocking of Phenom Agena (especially B2 stepping) makes not really fun. Even small increases in the reference clock can lead to reaching the limit of the processor clock. Many B2 processors have only one-can achieve up to two hundred more MHz clock frequency. Rarely create further copies, 3 GHz can be achieved virtually impossible.

But it is interesting that while the OC potential is usually very limited fails, the processors can be under volt but usually in the sense in efficiency, good. Phenoms in the B3 stepping (to recognize the number 5 on the third place of the model name -> e.g. AMD Phenom X3 Agena 87 5 0) generate on average higher clock speeds (3 GHz are not uncommon), but remain relatively far below expectations. It is therefore not surprising that the fastest-Agena Phenom clocked at just 2.6GHz (Phenom X4 9950 BE).

Agena processors generally have the problem that is usually not high reference clocks can be achieved. Often one reads even the fact that at 230 MHz the limit is already reached. With a view to the maximum clock rates which plays only a minor role, since one usually has previously had reached the limit of the processor (230 x 11.5 = 2645 MHz, which have managed most no longer Phenom X4 9600).

CPU and Northbridge multiplier

Both the CPU multiplier and the multiplier of the North Bridge. Die the Phenom Black Edition has a free multiplier. Thus, the overclocking of the CPU without increasing the reference clock and thus no change in the HT-Link and NB-stroke is possible. Of course, the way is still on the reference clock available, but is no longer necessary.

For all models of the Black Edition series (both Phenom and Phenom II) can change the multiplier of both bars both up and down, with all other models only to bottom. The change can either AMD Overdrive or K10Stat from the Windows's interface, one above uses existing BIOS options.
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Old 02-09-2010
Join Date: Sep 2005
Posts: 1,306
Re: Official Phenom and AM2/AM2+ Overclocking

The NB-multiplier

The NB-multiplier is set free on all currently available Phenom models in the standard operating either in 9 or 10. Until the release of AMD Overdrive 3.0 BIOS was the adjustment of the North-bridge multiplier only possible. Since version 3.0 offers the AMD tool also own a NB-option, so the clock can also be changed in the Windows (practice tests are still pending for this).
Almost all motherboards now offer options for the adjustment of the North Bridge-multiplier in the BIOS.

  • MSI K9A2 Platinum
  • Gigabyte GA-MA790FX-DQ6
  • Gigabyte GA-MA770-DS3
  • ASRock ALiveDual-eSATA2
  • ASUS Crosshair II Formula
  • ASRock A780FullDisyplayPort
  • ASUS Crosshair II Formula
  • Gigabyte GA-MA790GP-DS4H
  • Gigabyte GA-MA790XT-UD4P
Problems in the Overclocking

On the Internet you read in part that do not work high HT link. The reason seems simple: As soon as the HT link is set higher than the NB-stroke, does not boot the PC. Why this is so, opens up to this day is not complete. But the fact is that the practice shows exactly this behavior. Conversely, this means that one should use the current maximum Phenom multiplier 9 (or 10, depending on model) for the HT-Link (which is 1.8 GHz HT-Link at 1.8 GHz and 2.0 NB-stroke GHz HT-Link at 2.0 GHz does NB-clock).

Meanwhile, many motherboards will be a protective function is implemented, which prevents the HT link can be set higher than the NB-Multi. This ensures that users choose, they do not know the rule to be followed, but not provided for incorrect settings.

Prerequisites for the successful Overclocking

As with the K8, it is appropriate to make some basic settings in Mainboard bios. From personal experience suggest:
  • Disable Cool n Quiet
  • Disable virtualization
  • Set voltages manually
  • Manually set timings
  • Spread Spectrum Disable
  • MaxAsyncLatency MaxReadLatency or adapt to high levels
  • TRFC set to a high value
These settings are not mandatory. However, one runs the risk of failure to observe that one unintentionally gets into trouble because the system clock speeds and voltages can forgive autonomous, not what you want as a user. Therefore, it is useful to test the desired clock rates set until all the options and then manually turn on when needed as well as the Virtualization Cool n Quiet again.

Maximum reference clock at the Agena Phenom

Many will think that 264 MHz reference clock are not necessarily the killer. This will be said, however, that there is indeed a top result already. If one follows namely the results of the OC-Phenom closely, it is clear that eliminate many users already at around 230 MHz, the sails need.

The Phenom of the first generation is not able to reach high reference clocks. This is not strictly necessary, as all performance-relevant clock rates by multiplying or computing relationship will be formed. But in order to find the best combination of all the clock speeds, increased reference clock is quite reasonable.

Memory Voltage

The Internet spread the message that there may be tensions in memory of more than 2 volts to the failure of the CPU. So far, this point proved anything yet, but for some it should be happening already. The possibility is certainly, as the memory controller is in the CPU and therefore may have dependencies and interactions.

Many memory, especially low latency DDR2 Ram and a highly clocked memory, have already made a specification by the manufacturer of more than 2.0 volts. Here, the user should therefore exercise caution, since a loss of the CPU is not completely ruled out. While there are certainly far more than 2.0 volts with screenshots Vdimm, the tip should provide a current screenshot with rich 2.9 Volt Vdimm, which was used for several hours. And with no impact on the processor.


Those who are using a platform including AM3 DDR3 decide which are open to many possibilities. The decision is up to each user and personal preferences. When reference is made but that the choice of memory and the planned use area should be dependent. There are applications (such as WinRAR), which have little or no benefit from higher memory clock - but much of tighter latencies. For example, such applications would be DDR3-1600 CL9 with poison while they were happy with DDR3-1066 CL5 with or Cl6 forward. Other applications benefit in turn from high clocked memory and ignore the memory latencies formally. These applications would benefit from DDR3-1600 CL9 DDR3-1066 compared with Cl6.

It is always a mixture of the change of clock speeds and timings, in order ultimately to find the perfect setup. Since every critical cycle can be adjusted individually, poses some tests to find out the respective limits relatively easy to combine the end for the best performance. For this example was used DDR3-1552 with timings of 7-7-7-21. In such circumstances, any application can benefit a little.

While in a Command Rate of 1T DDR2 at DDR2-800 and higher was nearly impossible, this setting is relatively unproblematic DDR3. Even with four bars, each with two gigabytes of capacity 1T is possible. However, there is no guarantee this, nor for a high memory clock in general. However, it is worth a try in any case.

In general, AM3-user try the following things:
  • Memory voltage of 1.65 - 1.7 Volt against other settings
  • Smaller memory clock (e.g., DDR3-1333) in conjunction with a high reference clock
It has been shown that a memory voltage in the range of 1.65 volts can affect positive than higher values. One reason for this may be a reduced heating of the memory module, another could be the difference to lower CPU North Bridge (sitting in the know, the memory controller).

Likewise, it may be advantageous to place the setting for DDR3-1600 DDR3-1333 setting to use, but the reference clock adapted To ensure that you reach DDR3-1600 (240 MHz reference clock / 3 * 10 = 800 MHz memory clock). Some motherboards BIOS prepares the option for DDR3-1600, some problems, so that the alternative route is partly better advice.
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Old 02-09-2010
Join Date: Sep 2005
Posts: 1,306
Re: Official Phenom and AM2/AM2+ Overclocking

Recommended Tools :

Useful Tools

To come to regard the necessary information of the settings to offer these tools:

AMD Overdrive:

Now available in version 3.1.0. It can be used to read all important data. In addition, offer many options as voltages and clock speeds to overclock in Windows. AMD Overdrive sets new versions in advance as version 2.0.7 (Beta) a 7 series chipset, the in-house. Some features are only available on top when a ATi SB710 or SB750 with Advanced Clock Calibration (ACC) and one in a Black Edition Phenom is used.


Using K10stat can be manipulated as with the MSR editor of some K10 CrystalCPUID Register on-the-fly, so including an adaptation of VID_VDD and VID_VDDNB under Microsoft Windows is possible, largely independent of the firmware of the motherboard. K10stat dominated profiles for different P-States. The manipulation of the Registry shall however, be valid until the next reboot.


The small and there are now well established tool currently in version 1.52.4 for download. It can be used for quick reading of the clock rates. HT-Link and NB-stroke appear reliable. From the same manufacturer, there is a program called HWMonitor, which exists currently in version 1.15 and in a position existing temperature sensors.


Of course, any increase in stroke also be checked for stability. For this purpose, Prime95 is ideal, which it currently is in version 25.11. The program starts with the choice, "Just stress testing" a so-called independent worker thread per core.


Like the Phenom II X4 940, Phenom II X4 920 uses the same frequency for the internal server Bridge - 1.8 GHz, and supports the same set of memory types, including the DDR2-1067 SDRAM. No difference in these two processors and estimated the typical heat, set equal to 125 Tues Thus, standing at 30 dollars cheaper than its older brother Phenom II X4 920, really, in terms of features gives him only in clock speed. But in addition, AMD did not refer Phenom II X4 920 to the number of processors Class Black Edition. In other words in the Phenom II X4 is blocking overclocking the processor through simply increasing the multiplier.

On the one hand it is - enough bad news for overclockers. But on the other end to run overclocking it is not raised, but merely means that, as processors are Intel, overclocking Phenom II X4 920 should be by increasing the base frequency clock generator. However, the K10 architecture is not bad. The big problem is to look elsewhere and more specifically the side of the manufacturing process and operating frequencies. Let's be very clear again, AMD does not absolutely control the 65nm manufacturing process. While the production of chips totaling over 450 million transistors is already a huge challenge in industry, AMD is still failing to raise the frequency.

By trying to make any price native quad-core to stand out from Intel, AMD is royally feet in the carpet and Phenom is clearly handicapped by his too-low frequencies. Initially designed for a frequency of 2.4 GHz at launch, AMD has at the last minute canceled the Phenom 9700 is back on the model 9600 running at 2.3GHz.
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