# 1.65V i5 3570K



## bettz (Oct 18, 2012)

My friend gave me 4gbs of Kingston HyperX blu DDR3 1600MHz XMP DIMM KHX1600C9D3B1K2/4GX which i plan to use in my htpc build.

I've got a i5 3570k and the following motherboard Asus P8Z77-M have i cocked up  i've read that Ivybridge shouldnt be run on ram over 1.5v but im confused as people say 1.65v is fine  

Can anybody clear this up for me.


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## trickson (Oct 18, 2012)

bettz said:


> My friend gave me 4gbs of Kingston HyperX blu DDR3 1600MHz XMP DIMM KHX1600C9D3B1K2/4GX which i plan to use in my htpc build.
> 
> I've got a i5 3570k and the following motherboard Asus P8Z77-M have i cocked up  i've read that Ivybridge shouldnt be run on ram over 1.5v but im confused as people say 1.65v is fine
> 
> Can anybody clear this up for me.



What are you planing on doing? Man to put 1.5v is insane and to do 1.6v is just suicide!


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## brandonwh64 (Oct 18, 2012)

bettz said:


> My friend gave me 4gbs of Kingston HyperX blu DDR3 1600MHz XMP DIMM KHX1600C9D3B1K2/4GX which i plan to use in my htpc build.
> 
> I've got a i5 3570k and the following motherboard Asus P8Z77-M have i cocked up  i've read that Ivybridge shouldnt be run on ram over 1.5v but im confused as people say 1.65v is fine
> 
> Can anybody clear this up for me.



Just set the ram to 1333mhz CAS 9 1.5V and it should run without issues.


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## cdawall (Oct 18, 2012)

You could always try 1600 CL9 at 1.5-1.55v and see if it is stable. Ram doesn't always have to have the memory voltage at full spec..


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## MxPhenom 216 (Oct 18, 2012)

trickson said:


> What are you planing on doing? Man to put 1.5v is insane and to do 1.6v is just suicide!



hes talking about memory. Read the post, not the title.

OP it depends on the memory. Some kits say 1.65 so do 1.65. Some are 1.5v, and some some go as low as 1.3v


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## erocker (Oct 18, 2012)

I wouldn't know of an issue with running 1.65v RAM with Ivy Bridge. Heck, places like Newegg advertise some 1.65v RAM as being made for/compatable with Ivy Bridge. I've been running my RAM at 1.65v for a while now. No issue.


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## Binge (Oct 18, 2012)

There is a similar issue with the mem controller voltage vs memory voltage like we saw with the x58 boards.  Most motherboards if the mem controller is on auto will correct and balance for the difference in voltage.  Difference between the two should not be more than .5v.  That allows for the mem controller to be run at a minimum of 1.15V for 1.65V dram voltage


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## bettz (Oct 18, 2012)

So i should be ok to run the ram then?


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## Hood (Oct 23, 2012)

trickson said:


> What are you planing on doing? Man to put 1.5v is insane and to do 1.6v is just suicide!



He's talking about RAM volts


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## trickson (Oct 23, 2012)

Hood said:


> He's talking about RAM volts



Oh Okay .


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## Hood (Oct 23, 2012)

*Intel's way of covering their ass*



bettz said:


> i've read that Ivybridge shouldnt be run on ram over 1.5v but im confused as people say 1.65v is fine



Intel doesn't recommend using over 1.5v for RAM, but also says voltage over 1.65 will reduce the life of your processor, and possibly kill it quick, but I know people who go over 1.65 when overclocking without apparent damage.  I currently use 1.65v 1600 Kingston that's really just overclocked 1333 sticks with more voltage.  Right now 2400 Ram and up is all 1.65v, but you can get 8 GB of 2133/1.5v RAM for $56, with decent timings and latency.  That's the sweet spot - only a few bucks more than basic RAM, with low voltage and timings, such as the Intel Extreme Masters from Patriot.  Ivy Bridge is so efficient at using memory, you don't get much out of higher memory speeds, but you do get lower latency, and up to 25 GB/s throughput, which is much more than you really need.  I feel more comfortable using 1.5 volts and will soon upgrade to the 2133/1.5v.


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## hat (Oct 23, 2012)

1.5v is JEDEC standard for DDR3, so naturally Intel would back that standard. Intel spec allows for up to 1.65v. As Binge says, memory voltage must be within .5v of qpi/dram (memory controller) voltage, so the memory controller should be no less than 1.15v when vmem is 1.65v. If you had 1.6v memory you could attempt to run 1.1v qpi/dram. I'm not sure what would happen if you ran 1.1v qpi/dram and 1.65v memory. Is it just that vmem and qpi/dram voltage must be within .5v of eachother, or is it just that over 1.65v memory is dangerous? That's my own question left unanswered thus far.


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## Sasqui (Oct 23, 2012)

hat said:


> 1.5v is JEDEC standard for DDR3, so naturally Intel would back that standard. Intel spec allows for up to 1.65v. As Binge says, memory voltage must be within .5v of qpi/dram (memory controller) voltage, so the memory controller should be no less than 1.15v when vmem is 1.65v. If you had 1.6v memory you could attempt to run 1.1v qpi/dram. I'm not sure what would happen if you ran 1.1v qpi/dram and 1.65v memory. Is it just that vmem and qpi/dram voltage must be within .5v of eachother, or is it just that over 1.65v memory is dangerous? That's my own question left unanswered thus far.



Awesome thread, I'm learning here on the sidelines 

So If I bump my CPU to 1.2v, memory would be safe at say 1.7v?

I've gone out and bought 16GB of CL9 2133 DDR3 memory that is rated at 1.65v (it seems almost all of them are 1.65v).  On another note, I have yet to buy motherboard and CPU, LOL.


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## cadaveca (Oct 23, 2012)

hat said:


> 1.5v is JEDEC standard for DDR3, so naturally Intel would back that standard. Intel spec allows for up to 1.65v. As Binge says, memory voltage must be within .5v of qpi/dram (memory controller) voltage, so the memory controller should be no less than 1.15v when vmem is 1.65v. If you had 1.6v memory you could attempt to run 1.1v qpi/dram. I'm not sure what would happen if you ran 1.1v qpi/dram and 1.65v memory. Is it just that vmem and qpi/dram voltage must be within .5v of eachother, or is it just that over 1.65v memory is dangerous? That's my own question left unanswered thus far.



IVB is not X58 or P55, so none of this applies.

1.65 V ram is fine. Intel says max 1.85 V.


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## hat (Oct 23, 2012)

No, not CPU voltage. The two voltages that must be within .5v of eachother are QPI/DRAM (memory controller) voltage and memory voltage.


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## cadaveca (Oct 23, 2012)

hat said:


> No, not CPU voltage. The two voltages that must be within .5v of eachother are QPI/DRAM (memory controller) voltage and memory voltage.



Does not apply to 1155. Memory controller votlage is default 0.925 V, memory is 1.5 V, there goes that idea. 

Of course, QPI is not used any more.

To the OP, all you should have to do is enable XMP in BIOS. 1600 Mhz is default for IVB, and 1.65 V should be fine....has been for me since the launch.


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## EarthDog (Oct 23, 2012)

cadaveca said:


> Does not apply to 1155. Memory controller votlage is default 0.925 V, memory is 1.5 V, there goes that idea.
> 
> Of course, QPI is not used any more.
> 
> To the OP, all you should have to do is enable XMP in BIOS. 1600 Mhz is default for IVB, and 1.65 V should be fine....has been for me since the launch.


This. Spot on as usual.


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## bettz (Oct 23, 2012)

I ended up solving this when My friend gave me a set of 4GB G.Skill RipJaws 1600MHz DDR3 Dual he had lying around .


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## Wrigleyvillain (Oct 23, 2012)

Man I thought this was referring to CPU voltage at first!


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## Vlada011 (Oct 23, 2012)

I have Kingston 1.65V on 1600MHz, but only tree days more, than Dominator Platinum will change and that is 1.5V. Because 1.65V I set voltage manual to 1.5, 
XMP load 1.65V and for Intel is better 1.5V. I follow that story and it's not hard to listen and buy 1.5V if they say that is better. About some damage during keep on 1.65V I don't know and don't think on that. Intel say Yes 1.65V colud damage. I read that but I know lot of people keep on 1.65V.


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## brandonwh64 (Oct 23, 2012)

I am using Corsair 1600Mhz CAS 7 1.8V ram in my cruncher at work. Got it set at 1333mhz cas 9 1.5V easy


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## Sasqui (Oct 23, 2012)

cadaveca said:


> IVB is not X58 or P55, so none of this applies.
> 
> 1.65 V ram is fine. Intel says max 1.85 V.



I got to start a thread whilst I shop for IB motherboards, or should I just contact you directly?


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## cadaveca (Oct 23, 2012)

MAke a thread!


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## Binge (Oct 23, 2012)

Cad,

So what changed to offset the correlation between memory voltage and memory controller voltage.  Other than the defaults (which are different on my board than what was posted) do you have any hard numbers or long standing overclocks that use mem and controller voltages with a difference over .5V?


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## cadaveca (Oct 23, 2012)

Binge said:


> Cad,
> 
> So what changed to offset the correlation between memory voltage and memory controller voltage.  Other than the defaults (which are different on my board than what was posted) do you have any hard numbers or long standing overclocks that use mem and controller voltages with a difference over .5V?



Sure do have that. Many /SNBIVB system has more than that, as I stated above.  I've seen 0.860V- 0.950 V for IMC, and 1.5V is default...immeidately, any stock CPU goes outside of that ratio.


What changed? The sockets? The CPUs? That only applied to P55/1366; we've had 1155 for some time now(nearly 2 years), and no, it does not matter, since it works as I stated above.


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## Binge (Oct 23, 2012)

cadaveca said:


> Sure do have that. Many /SNBIVB system has more than that, as I stated above.  I've seen 0.860V- 0.950 V for IMC, and 1.5V is default...immeidately, any stock CPU goes outside of that ratio.
> 
> 
> What changed? The sockets? The CPUs? That only applied to P55/1366; we've had 1155 for some time now(nearly 2 years), and no, it does not matter, since it works as I stated above.



With X58 the memory controller voltage and mem voltage ratios were within the .5V.  That much is obvious and it is also very obvious the difference between the IMC and mem voltage with 1155 in some cases is well outside of the .5V.  For the most part the .5V rule was only applicable for users who were going over 1.5V on the x58 IMC which was known as the QPI.  I don't think I'll get an answer to my question here.  You have not stated how it works; you've just reposted some stock voltages and said nothing about overclocking tolerances.


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## cadaveca (Oct 23, 2012)

Binge said:


> For the most part the .5V rule was only applicable for users who were going over 1.5V on the x58 IMC which was known as the QPI.



Ah, well ,you know, QPI stands for Quick Path Interconnect...what the CPU's bus was called, not the IMC. QPI replaced the Front Side Bus.

http://www.intel.com/content/www/us...performance-quickpath-architecture-paper.html

Now we have BCLK.

The lack of that ratio to remain is because how those two things work together is differently. Nehalem had L3 cache on one side, and memory control on the other(physically), while with SNB/IVB L3 is connected to the memory contorller this time via the system agent, and is right next to the L3. Also, with SNB and IVB, the L3 runs at the same speed as the core, while on Nehalem the L3 ran at a seperate speed.

As to the exact reason why, no I cannot tell you, as Intel has not really disclosed that info at this point, other than that the whoel northbridge sub-sytem is now very much different. Personally, I think it's becuase the system agent decouples VTT from IMC.

I'm just an enthusiast, not an engineer, so I can only relate info that Intel gives, and I still do not have direct contact with them for this sort of information, unfortunately. Just another goal to attain. 

Might have something to do with them adding the PU, even I couldn't tell ya.

And with that said, you'll probably have to ask Intel directly on that one,  to get something other than "the electrical layout is different now".


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## Binge (Oct 23, 2012)

Found a bit of info from XS about user tested voltages vs intel standard.  Looking for more information on how the IMC communicated with which parts of the processor.  Physical placement of the components in the silicon are 1/2 of the equation.  Definitely interested in finding out some more facts about voltages and the new roll of the IMC as Cad has made the observation that it is a drastically different design.


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## cadaveca (Oct 23, 2012)

SIn posts here as well under the UID StevenB. That chart is here as well, too.

He's the only user really posting such stuff.


Part of it is that with the tuning warranty, and how these chips clock, there's really nothing to worry about. You're actually pretty safe from killing these chips....except that the raw CPU speed scales with votlage, even under high temps. This may cause some users to push too far, and shorten the lifespan of the chip drastically.

But otherwise, as long as you keep temps i ncheck, and know a bit about how voltages can fluctuate, there's not a lot you can do that is really going to hurt things.

Overclocking today is more about buying the right parts to work together, mostly memory and motherboard i nthat, too, and then getting some luck on how good your IMC is, or so it's been related by many othre reviewers...I still do not think I have found the max of my 3770K's memory controller. But then, maybe i have..still working on that one.


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## Binge (Oct 23, 2012)

Yeah if I had known that would have been one of the first things I posted.  Great to get anecdotal bits from users who have had the option of testing a number of chips.  Most of the x58 knowledge was trial & error which busted a number of chips.


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## cadaveca (Oct 23, 2012)

Binge said:


> Yeah if I had known that would have been one of the first things I posted.  Great to get anecdotal bits from users who have had the option of testing a number of chips.  Most of the x58 knowledge was trial & error which busted a number of chips.



That's always the case, but now there is actually so little left to user intervention, there's no a lot of info to be found. Intel has made it so easy, you jsut buy the ram you want...buy a decfent board, adn then set ram, and set turbo multis...and maybe some CPU voltage. Most users won't even have to play with IMC voltage much.


I run 2666 MHz daily with my 3770K, 10-12-12-35, 0.95 V on IMC. 10.05 V on VTT(stock votlage for both), and 1.65 V on ram. I can guarantee that any such concerns from the past and having that specific ratio between ram and IMC/VTT are long since gone.


In fact, you'll find many reports of VTT being what's needed to be adjusted when clocknig ram..not IMC voltage...


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## Sasqui (Oct 24, 2012)

cadaveca said:


> I run 2666 MHz daily with my 3770K, 10-12-12-35, 0.95 V on IMC. 10.05 V on VTT(stock votlage for both), and 1.65 V on ram. I can guarantee that any such concerns from the past and having that specific ratio between ram and IMC/VTT are long since gone.



You're running 32GB of 2133 CL9 G.Skill at that speed?  Nice...


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## cadaveca (Oct 24, 2012)

Sasqui said:


> You're running 32GB of 2133 CL9 G.Skill at that speed?  Nice...



ha, no, I was running, mhaven't updated system specs in a while.

I've never really ran less than 2133 MHz though, unless benchmarking.


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## Sasqui (Oct 24, 2012)

cadaveca said:


> ha, no, I was running, mhaven't updated system specs in a while.
> 
> I've never really ran less than 2133 MHz though, unless benchmarking.



I'm curious what I could get The G.Skill Sniper 2133 CL9 to run at using CL11


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## cadaveca (Oct 24, 2012)

Sasqui said:


> I'm curious what I could get The G.Skill Sniper 2133 CL9 to run at using CL11



Hard to say just by model number, depends on the ICs how much potential they might have.


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## EarthDog (Oct 24, 2012)

Sasqui said:


> I'm curious what I could get The G.Skill Sniper 2133 CL9 to run at using CL11


On your current rig, I wouldnt imagine a terrible amount more. On an IB, as I think those are Hynix IC's (not sure), those could easily see 2400Mhz+. The memory controller on SOME of those IB CPUs are mad good.


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## Sasqui (Oct 24, 2012)

EarthDog said:


> On your current rig, I wouldnt imagine a terrible amount more.



  My current rig only supports DDR2, the backstory...  I bought 32 GB of the stuff as I will soon buy a CPU and MB but haven't made up my mind yet.


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## Hood (Oct 25, 2012)

cadaveca said:


> 1.65 V ram is fine. Intel says max 1.85 V.



Somehow I missed where Intel said 1.85v is max for Ivy Bridge memory, could you point me to the article or tech document?  I was under the impression that the safe max is 1.65.  So if I can already overclock my basic 1.65v 1600 RAM to 1866, what happens if I bump the voltage to 1.7? (not gonna do it, just asking the question).  Will I be able to hit 2000 or maybe tighten the timings a bit by adding the extra juice?  And what am I gonna fry, the CPU, the RAM, or both?  Anyone out there tried this?


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## cadaveca (Oct 25, 2012)

Hood said:


> could you point me to the article or tech document?



There are only three or four on intel's site for each CPU??? It's not hard to find...

lots of guys benching with 1.8 or so, Maximus V Formula and Maximus V Gene even have 1.85 V TridentX profile....


Personally, I wouldn't recommend running it though. Intel says max VID for SNB is 1.525 or something, too, and I know that long-term that votlage will shortne the life of the chip.


With vDIMM, since it's kinda decoupled, I could seee hwo it's possible, since PLL is 1.8 V too...but I dunno 1000%. I do know that 1.85 V is listed in whitepapers though, if it hasn't been editted.


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