Westmere-EP & X58 Overclock Info
Let me start by saying thanks for reading this article. You can sign up and discuss this using the comment section [last page if I ever add pages]. I’ve decided to write this information regarding the X58 chipset and Gulftown\Westmere-EP. There is a lot of information about the X58 spreading around the net due to the recent “revival” of the platform. Long story short there are a ton of Xeons flooding the market. These Xeons are being replaced by newer Xeons based on newer architectures.
More than a likely a lot of server leases are up or companies have decided to upgrade and get rid of the legacy tech. So now you can get a 6core\12 logical core on the X58 platform for as low as $60-$80. Not only that, but these Xeons are beasts! The Xeons contain 12MB L3 cache and they fall on Intels “tick” process techology model meaning that Intel shrunk the die to 32nm from the previous “tock” 45nm (Tick-Tock). Most X58 upgraded to Sandy\Ivy Bridge. Some X58 users didn’t feel the need to upgrade since the performance gains and overclocking potential wasn’t much greater than Bloomfield-X58. The price didn’t seem worth it. Later the X79 released, supporting both Sandy Bridge and Ivy-Bridge “E” CPUs. X79 replaced X58, but this felt more like a side grade to many X58 users. You cannot overclock Xeons on the X79 platform due to the restrictive BCLK. You can overclock Xeons in the X58 since there is nothing restricting you from doing so.
So now X58 has been revived and more users are realizing that their nearly 7 year old platform will last more years. Here are some stats for my X5660:
- Socket: LGA1366-Socket B
- QPI Link: 2
- OPI Transfer Rate: 6,400 MT/s
- Bus Data Rate: 51,200 MB/s
- Hexa-Core + HT @ 3.2Ghz
- x24 CPU Ratio\Multiplier
- L3 Cache: 12MB
- IMC: DDR3-800\1066\1333 Triple Channel
- TDP: 95watts
- VID Max Voltage: 1.350v
I completely love this CPU and the X56xx in general. Westmere's are very power efficient. I will be updating this article well into 2015 so check back regularly for updates. I'll try to add pictures and things of that nature as well. So I will start with the first misconception, the recommended VID.
CPU Max Voltage & Power Guideline Misconception
Alright we will address the most common misconception I’ve seen across the web. Time and time again X58 users will point to a commonly used example provided by Intel, stating that the max voltage for Westmere-EP is 1.4v. Meaning that as long as you set the CPU voltage to 1.4 or below you processor will be fine. This is simply not true and users constantly misunderstand how the CPU actually performs and how Intel designed the CPU. So let’s get one thing correct 1.35v is recommended by Intel on their ARK pages. People spread 1.4v as the max incorrectly.
The reason 1.35v is the recommend voltage is because Intel said it is. Also one thing that is normally overlooked is the voltage spike. Voltage spikes can literally kill the CPU and\or the Motherboard + MB components. This is more prevalent by setting manual or dynamic vCore too high. Intel also included a feature that will hopefully prevent the CPU from frying [old tech, nothing new here]. If the CPU temperature is too high the processor will cause the PC to freeze or BSOD. Otherwise continued use at high temps will cause the CPU will degrade which is why throttling was introduced. However, throttling will not prevent voltage spikes. Vdroop also helps preserve the CPU life. vDroop will allow the CPU to operate under load at a lower voltage while preventing or avoiding spikes that will surpass the voltage set[not manual] in the BIOS. If you have LLC [Load-Line Calibration] set to AUTO[depends on settings] or Enabled then vDroop is DISABLED. AUTO can vary so either use Enable or Disable. This means that you could unknowingly damage your CPU over time. Some motherboards handle LLC better or worse than others.
The voltage spike for the 45nm and 32nm is 0.05v. Actually the 45nm could be 0.06v IIRC. Have you ever wondered why your PC shows a BSOD or freezes when you start a benchmark\stability tool? Well one of the most overlooked issues was the voltages spiking past your manually set CPU voltage. Another reason could be that you didn’t use enough vCore or several other settings. When your processor switches from an idle to load condition or vice versa, this can cause a spike. Well at least Intel states that the processor will have voltage spikes.
So why would Intel state that 1.4v is the max? Well Intel states this because 1.4v is the MAX VOLTAGE and they are respecting their own technology and guidelines. Now let’s do the basic math with vDroop and the correct use of VID in mind: 1.35v +(spike)0.05v = 1.4v! Of course this is backwards, but I'm trying to explain everything so that you'll understand it. I'll probably write up a overclocking guide regarding the voltage if enough people demand one. Therefore, Intel is correct when they state 1.35v as the max.
Now the way enthusiast or overclockers pass this information is in the wrong context. They spread the information as if it is used to be the maximum CPU voltage set in the BIOS. Time and time again I’ve seen overclockers use this as an excuse to reach their favorite frequencies. For instance here is the “wrong” way to use this information using manual voltage: (BIOS)1.4v+(spike)0.05v = 1.45v! Now the biggest problem is that you are now much higher than Intels recommended voltage of 1.35v. 1.35v is the max for my processor and I'm using it as an example. Also when this 1.4v is passed around the net enthusiast ignore all of the voltage guidelines set by Intel. With that being said you can continue to ignore the guidelines and overclock the hell out of your CPU for all I care. Just know that Intel repeatedly states and knows that your CPU will degrade over time so don't be surprised.
Thanks to vDroop and other voltage regulation guidelines, Intel developed a guideline to prevent the voltage from spiking past the voltage set in the BIOS. Whenever you remove vDroop and voffset then overclock your CPU using manual voltage you aren’t doing any favors for your CPU. Increasing the voltage is not the only answer to instability issues. Without vDroop and dynamic vCore there is practically nothing protector your CPU from negative and positive spikes. Users who run their gaming rigs with settings similar to what I just explained above will more than likely “lose” their stable overclocks over time due to degradation. Another overlooked issue is the time allowed for the voltage to spike. Long story short, if your voltage spikes for longer than the time allowed by Intel guidelines your PC will NOT be stable. This is crucial for high overclocks as the PC will unstable whenever you attempt to put a load on the CPU. So remember that voltage is not your only issue to worry about. There are other things that go behind the scene like negative and positive spikes. vDroop is a good thing so remember that. All of this information allows me to run fairly high overclocks while benefiting from the power saving features as well as the performance. Correctly overclocking your PC can extend the life of your server\workstation while allowing you to potentially lower your CPU temperature.
If you have any question or have more info feel free to post in the comment section or reach out to me. I'll be adding a lot more info to this article in the future.
George Orwell - 12\16\2014:
Well considering all the issues I've been having i will attempt to re-do my overclock without LLC then. Considering that LLC makes spikes -worse- then all the more reason. People with the X56xx are happy that that've been able to get a economical upgrade that actually even may have some life left in it for the next couple of years. Makes sense to make that life last as long as possible. (Unless we want to spend several hundred on the next iteration of intel six cores)