3930k and 64GB Ram - Bare with me

clayton006

[H]ard|Gawd
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Jan 4, 2005
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So questions for you all.

I have a 3930k normally with 32GB ram (Corsair Vengance 1600 kits) and I added another one for 64GB ram. I do a lot of work with VMs and I need ram badly. Problem is, seems that memtest fails whenever I have more ram than 32GB installed (and yes I know which first four slots to put the ram in to.

I've also noticed that memtest (version 4.3.3) shows the ram speed cut more than 50% when I put more ram in than the first four sticks (17000 MB/s vs 7200 MB/s). Not sure if that is by design either.

Is this more a problem about the IMC on my 3930k or a problem with the motherboard? If it is the IMC, I am eligible to trade my 3930k in for a 4930k, but I hesitate to do that as this 3930k has been a really good clocker (5.0GHz on water easily). Would the 4930k have a better IMC?

I've done all of this testing a stock clocks and voltages. Do I need to increase my VCCSA or VTT even at stock CPU speeds?
 
Your board is the ASRock x79 Extreme 11, right?

This guy also seems to be having ram issues (skip to 2:55) and he is also using the Corsair Vengeance stuff.

He mentions that after fighting to get the board to recognize his Corsair stuff his ram speeds got cut in half as well. After very selective ordering of the sticks he got it to work.

Therefore i would definitely focus on the board and/or memory sticks and not the CPU.
 
And why do you think I last 3 months reading articles and looking at OVL lists. I want to add 32 GB when DDR3 would be replaced by DDR4 and possibly some people would sell them cheap. Of course, this means sellecting some RAM now which would be fine with these unknown chips year later, and Quad channes on high speed is PITA. It's MUCH harder to plug 8 sticks into a X79 board and force them to work well as quad channel, than plug 4 sticks of high speed RAM into a Z87 board.

Decreasing speed, and increasing CL often helps. Reordering sticks to get better compatibility occasionally works as well.

You are not first one who is screaming murder about this, and you'd be not last one to complain it takes about 7 day of testing to get it right.

Generally, it's important to use the same speed and CL modules. Then of course because there are two stick per channel, they must work well together. DDR4 will not have this problem. It uses PPP protocol and either, you'd get 4 slots plug into them 4 sticks to get quad channel, and if you need more buy bigger sticks and replace them, or you'd get RAM with command buffer which removes these problems, but introduce additional latencies. Thus someone might be in situation when he tests his RAM and compare to DDR4 quad channel speed and finds rather small difference.

Well considering DDR4 would start at 2133, an additional latency would be PITA.
 
We'll I've got about 16 sticks here because I built other computers with the identical ram specs. I'm going through them all. I'm hunting down now a possible bad stick. Will see how it goes. Worst case I'll hobble along with 32GB of ram until Haswell E and DDR 4 like you mentioned above. Thanks for the YouTube link as well.
 
I am having a similiar issue with my ASROCK Extreme 6, except I have an i7-3820. It seems to have specific issues when using 8GB sticks.

I have come to the conclusion that even the latest BIOS has compatibility issues.

As for the slowing down when you add the other 32GB, it is because it is completely unstable.

With my 3820, even 32GB was unstable. After messing around with every possible setting for a few days, I discovered that I needed to set the RAM sub-timing "tCCD" to 1 and it magically cured my stability problems when running the RAM at 1600.

I am pretty sure no guides even mention adjusting the sub timings, at least none that I have seen.

edit: here is a link to the thread I started: http://hardforum.com/showthread.php?t=1780027

I am using HCI memtest for testing my RAM since it has proven time and time again that it finds issues a whole lot faster than memtest86/86+. If really unstable, it will find issues withing a few seconds. If only a bit unstable it usually finds issues within 10-15 minutes or so. The only downside is that the version that runs in Windows can only use 2GB per copy, so you have to run multiple copies to test you RAM.
 
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On my memtest screen what should I see for a single stick in per channel on my 3930k for 1600mhz ram. Looks like my 3570k shows 19000 MB/sec and my 3930k shows 16000 MB/sec. Seems like my 3930k should have more bandwidth but what do I know lol.
 
That 3930k bandwidth number look a bit low.

Is that with all 8 slots populated?
 
On my memtest screen what should I see for a single stick in per channel on my 3930k for 1600mhz ram. Looks like my 3570k shows 19000 MB/sec and my 3930k shows 16000 MB/sec. Seems like my 3930k should have more bandwidth but what do I know lol.

Well, the 3570k is an IB, and the 3930k is SB-E. Isn't the memory controller on IB and IB-E slightly faster than on SB-E?

If so, that wouldn't surpise me if you are checking the speed in single channel mode.

Also, your 3930k set up may be setting the timings slightly looser than with the 3570k set up.

I also woudn't hold much stock in the memtest speed scores.
 
Perhaps he should check a speed in single channel mode, just to test it.
 
And why do you think I last 3 months reading articles and looking at OVL lists. I want to add 32 GB when DDR3 would be replaced by DDR4 and possibly some people would sell them cheap. Of course, this means sellecting some RAM now which would be fine with these unknown chips year later, and Quad channes on high speed is PITA. It's MUCH harder to plug 8 sticks into a X79 board and force them to work well as quad channel, than plug 4 sticks of high speed RAM into a Z87 board.

Decreasing speed, and increasing CL often helps. Reordering sticks to get better compatibility occasionally works as well.

You are not first one who is screaming murder about this, and you'd be not last one to complain it takes about 7 day of testing to get it right.

Generally, it's important to use the same speed and CL modules. Then of course because there are two stick per channel, they must work well together. DDR4 will not have this problem. It uses PPP protocol and either, you'd get 4 slots plug into them 4 sticks to get quad channel, and if you need more buy bigger sticks and replace them, or you'd get RAM with command buffer which removes these problems, but introduce additional latencies. Thus someone might be in situation when he tests his RAM and compare to DDR4 quad channel speed and finds rather small difference.

Well considering DDR4 would start at 2133, an additional latency would be PITA.

DDR4 is likely to be really cool but it doesn't help him with his current issue.

OP -
I have a similar setup (see sig) and had no issues but I used 8 sticks from all the same manufacturer, bought at the same time. That might help.
 
OP,
Give this other [H] thread a look.

Forum member cyclone3d appears to have same board and use case. He also appears to have had some progress in getting 64GB ram stable.
 
I got 64gb 8 sticks of 1866 ram and a 3970x cpu on a asus rampage 4 extreme.

The machine will not power all 8 sticks with out the so called EZplug2 connector.

it is a floppy connector asus puts on motherboards to give extra power to the ram slots.

it is Corsair platnuim with out the plug on my machine only 4 sticks light up correct. (the ram has LEd lights) the ram is also not that stable with the power plugged in it is stable and can be over clocked just fine. I run hardcore 3d rendering on the machine for days at a time overclocked and all 64gb of ram shows up

I am not sure about your asus motherboard. if you have and extra ram power socket or PCI express power socket plug it in. the manual will say what they are for all ones asus has labeled Extreme may them.
 
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I have a Rampage IV and have 32GB.

I have no stability problems.

I would think its the RAM or your board. With that much RAM slow your timing down a tiny notch and see what happens.
 
Also look on your motherboards RAM compatibility listing. They show if the Vengeance is truly been quality tested with your board.

It does make a difference.
 
We'll there isn't a ton that is certified. I'm trying out some crucial ballistix ram. Supposedly they are samsung chips. Worst case if these don't work I'll go with the Kingston pack from new egg and give those a shot.
 
Does it run at 1333 JEDEC spec? I would bump the VCCSA to 1.200V and try that. Don't forget 1600 is an overclock setting for SB-E and they are not known for strong IMC when it comes to high speed/high density sticks.
 
My corsairs would run through the first pass in memtest just fine on either 1600 or 1333. About 2 hours after the first whole round of tests pass there is usually one error.

My Crucials have completely passed the first round. Going to see how far they go into the second.
 
I believe my VCSSA is at 1.20 on auto in this board. I've been testing just 4 sticks (32gb). If it keeps flaking out after the first test I may swap out for a 4930k and see how it goes.
 
We'll it did two full passes of the Crucial ram in 7.5 hours with no errors. I will probably throw in the other 32gb of the same and let it test overnight and all day tomorrow.
 
We'll it did two full passes of the Crucial ram in 7.5 hours with no errors. I will probably throw in the other 32gb of the same and let it test overnight and all day tomorrow.

Please let us know the results as many of us want to know how it ends up resolving for you.
 
We'll it did two full passes of the Crucial ram in 7.5 hours with no errors. I will probably throw in the other 32gb of the same and let it test overnight and all day tomorrow.

Sweet. I would not call it fully stable from just the RAM tests though, especially if using memtest86+.

I have been running HCI memtest in Windows while doing other stuff. 6 instances bring my 3820 up to around 80% CPU usage.

Throw in Netflix or Youtube, and even though I can pass the RAM tests overnight, it took some more tweaking on the RAM and CPU side to get it fully stable when the CPU is running at almost 100%.
 
I use HCI memtest as well, I just run enough instances to fully load up my RAM, which is probably easier for me to do since I'm running 8x4gb. It does peg my CPU at 100% though, and my system thoroughly lags when its testing. I let it run overnight.

Either my CPU does not like running 8 sticks above 1333 mhz or my RAM doesn't like running above 1333 mhz. I believe it's my CPU, because I'm able to run the RAM at 1333 CAS 8 with 1.425 V and stock VCCSA, even though my RAM is rated for 1333 CAS 9 at 1.65 V.
 
I've had some mixed results with the accuracy of the HCI test on my dual Xeon system in the past. I may use it again in the mid-term but I believe since I'm not pushing any limits with this RAM I'll be okay for the most part.

I've been at work for a while but before I left it had finished 1.25 passes in 7.5 hours with 64GB and so far so good. Will check it when I get home this afternoon.
 
Well it made two full passes in memtest with all 64gb installed with no issues. I should be good to go then. Will watch the system over the next few days.
 
Okay so another problem popped up which I may start a new thread for. If I cold boot my system it will flake out after post, and keep blue screening and reboot.
In the midst of this cycle, if I hit del to go into UEFI and then hit save settings, the system will auto power down, then come back up and work flawlessly....

Very strange. It also wakes back up from S3 sleep just fine as well. Any ideas on this weird behavior? I've had this board and CPU for a while so not sure why all of the sudden it wants to do that.

I will mention before, this system would just lock up on cold boot trying to load windows (but would never BSOD). Once I would power cycle it, it would boot fine. My SSDs are okay. Maybe I will reformat at some point.
 
I've experienced something similar, but in my case, it doesn't get to Windows. It would start and shut down, and then after several tries it'll say overclock failed. I would then go to the bios and save the overclock settings, and it'll work perfectly after that. I never really figured out why it does that, removing the memory overclock was the only solution I could get.

This did not happen on this system, but on a i7 920 system with a MSI Big Bang Xpower with the same RAM I'm using now.
 
Yeah not sure what is going on but I'm willing to live with it as I usually just put the computer to S3 sleep anyway. I'm just really hanging on for haswell E anyway.
 
Sounds like maybe something is not initializing correctly when you first turn on the power.

It could be that some connection needs to be reseated (RAM, MB Power, HDD or SSD power or data cables, a card, CPU).

Could always be that your power supply is starting to have issues as well. Maybe one voltage has dropped off a little bit or you are getting more noise than you used to.

I would try bumping voltages in BIOS around one at a time. Not necessarily just upping them, try each one at one step lower as well.
 
Using Sisoft Sandra benchmarks I was getting 21 GB/sec of memory bandwidth with 64GB installed. I went back to 32GB and I see a 45 GB/sec memory bandwidth number. I know that is pretty typical with x79 but still worth mentioning.

Thanks everyone for the assistance!
 
I got 64gb 8 sticks of 1866 ram and a 3970x cpu on a asus rampage 4 extreme.

The machine will not power all 8 sticks with out the so called EZplug2 connector.

it is a floppy connector asus puts on motherboards to give extra power to the ram slots.

it is Corsair platnuim with out the plug on my machine only 4 sticks light up correct. (the ram has LEd lights) the ram is also not that stable with the power plugged in it is stable and can be over clocked just fine. I run hardcore 3d rendering on the machine for days at a time overclocked and all 64gb of ram shows up

I am not sure about your asus motherboard. if you have and extra ram power socket or PCI express power socket plug it in. the manual will say what they are for all ones asus has labeled Extreme may them.

DAMN maybe my c2 3930k could have ran 32gb 8dimm... ... DAMN! it did 8 dimms samsung greens at 2133 2m stable
 
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