Overclocking Xeon X5482

[Pan_Melas]

Good day to all

I have to admit that I have not seriously been involved with overclocking, despite my intentions in the past, which remained just that: Intentions. Therefore, if I write any "stupid" words or phrases, I'd like to have moderators' understanding.

The main subject, now.
Short time ago (less than two months) I purchased a - 2nd hand - Intel quad-core Xeon X5482 processor (3.2 GHz, 12MB cache, 1600 MHz FSB, Stepping SLANZ-150W max. TDP), of the Harpertown family. As we all know, Xeons of this family work on motherborads with socket LGA771. However, a relatively recent "modding" has become trendy. With a simple adaption, Xeons can work on motherboards with socket 775, provided that these motherboards are equipped with one of the advanced chipsets of the 775 platform (that is: Intel P45-P43-P35-P31-G45-G43-G41-G35-G33-G31, nForce 780i-750i-630i, GeForce 9400-9300). Motherboards with other, older or inferior chipsets, simply cannot see a Xeon in their BIOS. More details for this "modding" can someone find in several links, if someone "googles" with the key words: "LGA771 to LGA775". For example, one of these links is the following:

http://www.delidded.com/lga-771-to-775-adapter/

I have installed this CPU on a newer and advanced (for its time) motherboard with s775, the Gigabyte GA-EP45T-UD3R. It is a motherboard with DDR3 slots only (up to 16GB total memory capacity and up to 2200+ MHz - I am going to use 4 DIMMs of Corsair Vengeance DDR3 CMZ16GX3M4X1600C9 with XMP profile, 4GB each, total 16GB), with FSB up to 1600 MHz, and so on. This motherboard, as all mobos of this level, gives the user the ability for an advanced and analytical overclocking via its special menu item of Gigabyte in the BIOS, called "M.I.T. - Motherboard Intelligent Tweaker". With this, the user can see, control and adjust the following CPU parameters (I am referring only to the CPU, because this advanced menu item also supports overclocking to the other subsystems of the motherboard, such as RAM memory, chipset, PCI-E slot etc., which for the present remain out of this discussion):

- CPU Clock Ratio It is usable when the CPU clock is unlocked. However, I found out that the clock of my CPU is locked. Therefore, I will probably not be able to use this function.
- Fine CPU Clock Ratio (in combination with the above item, it allows micrometric adjustment of the clock ratio at 0.5 steps, i.e. from 8x to 8.5x)
- CPU Host Clock Control. Enables or disables the control of CPU host clock. Enabled will allow the CPU Host Frequency item below to be configurable.
- CPU Host Frequency (Mhz). Allows you to manually set the CPU host frequency. This item is configurable only if the above item is enabled. For my CPU it must be set to 400 MHz for normal operation (8 x 400 = 3200 MHz or 3.2 GHz)
- CPU Clock Drive (it allows the adjustment of CPU amplitude and of the North Bridge from 700mV up to 1000mV, with default 800mV)
- CPU Clock Skew (Allows the user to set the CPU clock prior to the North Bridge clock. Options are: 0ps~750ps. Default: 0ps)
- MCH Clock Skew (Allows the user to set the North Bridge clock prior to the CPU clock. Options are: 0ps~750ps. Default: 0ps)
- Load-Line Calibration (Enables or disables Load-Line Calibration. Enabling this feature adjusts Vdroop, keeping the CPU voltage more constant under light and heavy CPU load. Disabled sets the CPU voltage following Intel specifications. Default: Disabled. I am not sure if I know what this exactly does and if it is connected with the next 3 items)
- CPU Vcore (Default: Auto. I suppose that this item controls and adjusts the voltage of the CPU core, which, in the case of Xeon X5482, is between 0.85V and 1.35V, with standard operation at 1.2V)
- CPU Termination (Default: Auto. I don't know what this exactly does)
- CPU PLL (Default: Auto. Also, I don't know what this exactly does)
- C.I.A. 2 (CPU Intelligent Accelerator 2). It is designed to control and adjust the performance of the CPU, depending on its load and it has 5 options: Disabled-Cruise-Sports-Racing-Turbo-Full Thrust. In these options, the CPU frequency is gradually increased, depending on the option and it can reach up to 19% more.

These are the basics, where the user can use. From the above parameters, I would like to clarify the following:

1) If I want, can I use all or only some of of them? And if yes, which ones?

2) Scoping in a mild-to-moderate overclocking (i.e. from its standard 3.2 GHz to go up to 3.6 or 3.8 GHz), except the CPU clock adjustment, which I suppose it will alter the CPU frequency, what other item must I consider, so that the CPU clock change harmonizes with other parameter or parameters?

3) If I finally do the overclocking, will it be necessary to alter (or adapt) the other subsystems of the motherboard (i.e. RAM or PCI-E BUS), or can I leave them untouched?

Thank you in advance.

(In order to avoid unnecessary discussions, I have taken care of the CPU cooling, so that higher temperatures shall be controlled).

 

[tomkis90]

All server CPUs are locked. That may change in the future, but for now do not get your hopes up on OCing a server chip.

 

[Pan_Melas]

All server CPUs are locked. That may change in the future, but for now do not get your hopes up on OCing a server chip.

Thank you, for your message, tomkis90. You are right on this matter. Besides, I have already noted that:

.......
- CPU Clock Ratio It is usable when the CPU clock is unlocked. However, I found out that the clock of my CPU is locked. Therefore, I will probably not be able to use this function.....

However, the scope of this discussion is whether I can O/C the Xeon or not and at which level, with or without altering the other subsystems.

Any suggestions will be highly appreciated.
-

 

[syphon85]

Hi,

I'm currently experimenting with the same Xeon X5482 3.2GHz (SLANZ) processor (reads as unlocked in my bios with E0 stepping) on my Asus P5Q Pro (P45 chipset) motherboard with Win 7 Pro 64-bit OS. I went to the trouble of flashing the bios with a modded rom which is patched with the Xeon processor microcode. Works fine on defaults, and without changing anything else i can change the CPU host clock from 400 to 425 and achieve 3.4GHz, and it's very stable.

However, i'm trying to push it a little harder than that and had my sights set on 4GHz. After experimentation i think this might be impractical and have decided to aim for either 3.6 or 3.8. At first 3.8 was equally un-achievable as the bios wouldn't even post with a whole host of tweaks. But I was able to get 3.6 by changing the FSB strap clock to 333MHz, CPU clock to 450MHz, and cpu vcore to 1.285v (from searching online i found the default to be 1.25v). I also had to tie down the clock on my memory which in reality is 1066 with 5-5-5-15 timing at 2.1v at default. This i set to something like 1150. I also tried with lower settings like 950 but if anything this was less stable. I should also mention I still have speedstepping enabled so the bios is taking care of the multiplier (auto), depending on workload this is dynamically changing from 6.0 to 8.0 in the OS.

Computer boots into OS, but stress testing with IntelCPUBurnTest showed possible instability. It seems to me that with the right tweaks this could be made to work but as core temps were still within tolerance (below 70c with H60 Corsair water cooling) I decided to take what i'd learn't and push on with 3.8GHz.

I'm currently running vcore at 1.32v (going to lower this if possible but i've seen reports of people taking it up to 1.40 to achieve 4.0GHz on a double cpu Skulltrail mobo), have introduced a pll voltage of 1.15v which i now believe is well below what the board was doing when still in auto. This was enough to get it to boot in to OS for a minute or so before blue screening with memory error. Further increases may yield greater stability, and i'm going to trial the cpu clock skewing to fix the crashing under load.

It's a work in progress but as there is so little information on this subject online, i thought i'd share my initial finding in the hope others might chip in with their success stories!

 

[Pan_Melas]

Hi,

I'm currently experimenting with the same Xeon X5482 3.2GHz (SLANZ) processor (reads as unlocked in my bios with E0 stepping) on my Asus P5Q Pro (P45 chipset) motherboard with Win 7 Pro 64-bit OS. I went to the trouble of flashing the bios with a modded rom which is patched with the Xeon processor microcode. Works fine on defaults, and without changing anything else i can change the CPU host clock from 400 to 425 and achieve 3.4GHz, and it's very stable.

However, i'm trying to push it a little harder than that and had my sights set on 4GHz. After experimentation i think this might be impractical and have decided to aim for either 3.6 or 3.8. At first 3.8 was equally un-achievable as the bios wouldn't even post with a whole host of tweaks. But I was able to get 3.6 by changing the FSB strap clock to 333MHz, CPU clock to 450MHz, and cpu vcore to 1.285v (from searching online i found the default to be 1.25v). I also had to tie down the clock on my memory which in reality is 1066 with 5-5-5-15 timing at 2.1v at default. This i set to something like 1150. I also tried with lower settings like 950 but if anything this was less stable. I should also mention I still have speedstepping enabled so the bios is taking care of the multiplier (auto), depending on workload this is dynamically changing from 6.0 to 8.0 in the OS.

Computer boots into OS, but stress testing with IntelCPUBurnTest showed possible instability. It seems to me that with the right tweaks this could be made to work but as core temps were still within tolerance (below 70c with H60 Corsair water cooling) I decided to take what i'd learn't and push on with 3.8GHz.

I'm currently running vcore at 1.32v (going to lower this if possible but i've seen reports of people taking it up to 1.40 to achieve 4.0GHz on a double cpu Skulltrail mobo), have introduced a pll voltage of 1.15v which i now believe is well below what the board was doing when still in auto. This was enough to get it to boot in to OS for a minute or so before blue screening with memory error. Further increases may yield greater stability, and i'm going to trial the cpu clock skewing to fix the crashing under load.

It's a work in progress but as there is so little information on this subject online, i thought i'd share my initial finding in the hope others might chip in with their success stories!

Although I know that it has been a long time since my first post on this matter, I am refreshing this thread, quoting your words, in order to ask you if you have achieved what you are initially describing, i.e.your final results with the X5482 O/C (including the settings for voltage and memory speed).

Will you be able to post here your results, in case you have achieved a stable system that works OK?
If yes, please, post as many details as you can, including RAM model, type and settings, voltages, your final choice for cooling method, etc.

This will help me to make my system working correctly because until now I have not been able to O/C my Xeon, been afraid that I may do something wrong and get a disaster at the end.

Thanks in advance.