memory slots failing - Is the memory controller on the motherboard or in the CPU (Intel 3930K CPU, X79 chipset)

x509

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What I want to know is where the memory controller is and why the memory slots are failing. I'm asking because I want to sell the board and CPU, but only if the parts are good. Here is why I'm asking.

My current system is built around an ASUS P79Pro motherboard with an Intel 3930K CPU. FWIW, it has never been overclocked. I built this sytem with 4 x 8GB RAM sticks. The motherboard has 8 memory slots, and is quad channel. I populated slots A1-D1. Slots A2-D2 would be used if I wanted to add more memory sticks, which i have never done.

The system was stable for years until about a year ago, when the Control Panel System applet reported only 24 GB and then only 16 GB. I spent too much time with Memtest86 trying to find 2 good memory slots for A1-D1. That was maybe six months ago. Now System applet reports only 8 GB system memory. (I'm planning to replace this board with an ROG Strix-E X570 and AMD CPU quickly.)
 

Denpepe

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The memory controller is on the CPU, but that does not mean everything, some boards warp and as such make bad contact or the cooler might be aplying uneven pressure, you could try reseating the CPU to see if that does anything, don't overtighten the cooler
 

vick1000

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Memory errors are commonly due to voltage flux that is out of spec for the chips, thus could be the RAM itself, the controller, or the motherboard, even the PSU lower voltage rails.
 

viivo

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Look at the socket pins from different angles with a bright light. Also check the bottom of the CPU in case some thermal paste made its way onto the contacts.
 

x509

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Memory errors are commonly due to voltage flux that is out of spec for the chips, thus could be the RAM itself, the controller, or the motherboard, even the PSU lower voltage rails.
I tested out all four memory sticks in a known good RAM slot, and all four are good. I used memtest86
 

x509

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Look at the socket pins from different angles with a bright light. Also check the bottom of the CPU in case some thermal paste made its way onto the contacts.
OK, I plan to do that as soon as I can. I'm also resigned to the fact that I need to replace the motherboard/CPU and RAM very soon. I hope to sort out all my choices in 2-3 days and order parts.
 

Furious_Styles

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OK, I plan to do that as soon as I can. I'm also resigned to the fact that I need to replace the motherboard/CPU and RAM very soon. I hope to sort out all my choices in 2-3 days and order parts.
Probably do need to replace it. Unless you can use C and D slots without issue. Lots of times only one bank of memory fails.
 

thesmokingman

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Keep in mind that systems don't run forever and eventually their lifespan will fall off a cliff. My old RIVE ran forever it seemed then issues cropped up fast. First the cpu header died, luckily I still had the cpu opt header. The the soundcard let go, switched to a soundcard. And this board was under water its whole life.
 

x509

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I'm talking about memtest.
Yes. Memtest is what I have been using in various rounds of RAM stick/memory slot testing. Frankly I've spent too much time doiong all these tests on a motherboard/CPU/RAM that needs to be replaced. I still intend to do the tests in post #2. If that fixes the system, I may keep the motherboard for spare/backup use.
 

vick1000

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Yes. Memtest is what I have been using in various rounds of RAM stick/memory slot testing. Frankly I've spent too much time doiong all these tests on a motherboard/CPU/RAM that needs to be replaced. I still intend to do the tests in post #2. If that fixes the system, I may keep the motherboard for spare/backup use.
I am saying memtest is a waste of time. Better of testing single sticks in single slots with Prime blend.
 

Wooshoo

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I am saying memtest is a waste of time. Better of testing single sticks in single slots with Prime blend.
So I have heard for years that memtest86 is gospel. What changed and is there a particular reason to use blend in prime rather than large fft? How long do you run until you consider it good?
 

GiGaBiTe

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So I have heard for years that memtest86 is gospel. What changed and is there a particular reason to use blend in prime rather than large fft? How long do you run until you consider it good?
Memtest86+ (www.memtest.org) is the best memory test, I have no idea why he thinks Prime95 is good for testing memory, because it's not. Not only can Prime95 NOT test anywhere close to all of the system's memory (because Windows and anything else running), it can't tell you where exactly in the system memory map that bad memory is detected.

If you have random memory slots failing, I'd suspect either the memory slots have tarnish on the socket pins, or the motherboard has warped and there's a bad socket connection. I'd recommend removing all of the memory modules AND the CPU and hosing down the memory slots and CPU socket with Deoxit Gold or CRC Precision Lubricant, both of which are designed to remove oxides and tarnish from electrical connections. Let the board soak for a night or so before reassembling it.

Here in central Texas, the humidity is so high that I constantly have problems with tarnished and oxidized connectors creating headaches. I usually have to treat my vintage computer gear with deoxit gold if it has been sitting awhile or memory modules have errors, ISA/PCI/AGP cards don't work properly, etc.
 

x509

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So I tried to fix the problem by removing and reseating the CPU. Now the sucker won't boot! :mad: Since I was doing this just to see if this old motherboard/CPU/RAM could detect all four memory sticks, I just gave up for now. I need to install my new ROG X570 Strix-E and concentrate on the new build.
 

Wade88

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^Get a magnifying glass and a bright light you might have bent some zif socket pins.
 

Wade88

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If you have random memory slots failing, I'd suspect either the memory slots have tarnish on the socket pins, or the motherboard has warped and there's a bad socket connection. I'd recommend removing all of the memory modules AND the CPU and hosing down the memory slots and CPU socket with Deoxit Gold or CRC Precision Lubricant, both of which are designed to remove oxides and tarnish from electrical connections. Let the board soak for a night or so before reassembling it.

Here in central Texas, the humidity is so high that I constantly have problems with tarnished and oxidized connectors creating headaches. I usually have to treat my vintage computer gear with deoxit gold if it has been sitting awhile or memory modules have errors, ISA/PCI/AGP cards don't work properly, etc.
this is good except that air conditioners remove humidity in the conditioned space they make systems that will run until the humidity is below a set point. If it works in AR it will work in the wetter parts of TX too.
 

pendragon1

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replace the cmos battery and do a good bios clear. battery out, hit the power button and let it sit for a few minutes. put battery in and try again.
 

vick1000

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Memtest86+ (www.memtest.org) is the best memory test, I have no idea why he thinks Prime95 is good for testing memory, because it's not. Not only can Prime95 NOT test anywhere close to all of the system's memory (because Windows and anything else running), it can't tell you where exactly in the system memory map that bad memory is detected.

If you have random memory slots failing, I'd suspect either the memory slots have tarnish on the socket pins, or the motherboard has warped and there's a bad socket connection. I'd recommend removing all of the memory modules AND the CPU and hosing down the memory slots and CPU socket with Deoxit Gold or CRC Precision Lubricant, both of which are designed to remove oxides and tarnish from electrical connections. Let the board soak for a night or so before reassembling it.

Here in central Texas, the humidity is so high that I constantly have problems with tarnished and oxidized connectors creating headaches. I usually have to treat my vintage computer gear with deoxit gold if it has been sitting awhile or memory modules have errors, ISA/PCI/AGP cards don't work properly, etc.
Because Memtest does not stress the memory controller on the CPU, or the rest of the subsystem.
 

GiGaBiTe

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this is good except that air conditioners remove humidity in the conditioned space they make systems that will run until the humidity is below a set point. If it works in AR it will work in the wetter parts of TX too.
Sure, if you want to be a mummified popsicle with a huge electric bill. I have central air AND a window unit to assist in our hot summers, it's hard to get the humidity below 60%. I have another window unit in the garage that will fill a five gallon bucket in just a couple of hours.

Because Memtest does not stress the memory controller on the CPU, or the rest of the subsystem.
Memtest most definitely stresses the memory controller, how do you think it writes so much data to every memory module so quickly? It is even more stressful in SMT mode where every core/thread is used to test memory.

Prime95 is not a valid method of testing memory, it is known to give false positives, especially in older versions of the software. And even if it does show a problem, it won't show you where it is and you're back to where you started. Memtest will tell you the exact location of the memory failure, and since the memory map is linear in most cases, it's super easy to figure out which stick is defective. Heck, you can use it to figure out which memory chip on which stick is defective.
 

bigdogchris

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I seem to remember talk here several years ago about a memory issue where some slots were not detected. I can't remember if it was x58 or x79 boards though.
 

x509

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I seem to remember talk here several years ago about a memory issue where some slots were not detected. I can't remember if it was x58 or x79 boards though.
So I just did a search on this issue for X79 motherboards, and sure enough, I got a lot of hits. Since I'm now focused on my new build, I'm putting this item on my "to do sometime" list. :) Thanks for the suggestion.
 

Wade88

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Sure, if you want to be a mummified popsicle with a huge electric bill. I have central air AND a window unit to assist in our hot summers, it's hard to get the humidity below 60%. I have another window unit in the garage that will fill a five gallon bucket in just a couple of hours.



Memtest most definitely stresses the memory controller, how do you think it writes so much data to every memory module so quickly? It is even more stressful in SMT mode where every core/thread is used to test memory.

Prime95 is not a valid method of testing memory, it is known to give false positives, especially in older versions of the software. And even if it does show a problem, it won't show you where it is and you're back to where you started. Memtest will tell you the exact location of the memory failure, and since the memory map is linear in most cases, it's super easy to figure out which stick is defective. Heck, you can use it to figure out which memory chip on which stick is defective.
You're doing it wrong, your central(!) air conditioning has a condensation drain tube that runs to the outdoors. There is no bucket to fill so long as that drain tube remains clear and is appropriately sized. You might want to look at a different insulation strategy or obtaining a more powerful central air conditioning system. Even your window units could use a drain tube, the buckets are for less humid places... Your house was built improperly for the location if it's HVAC system can't handle your weather.

You don't have to sit under an air register, you can sit further away from them or you can use ceiling fans, desk fans, or standing fans (or a combination) to help spread the cool air around your office or wherever you lurk and keep your equipment. It gets as humid here as it does there, non-natives that transferred here and tried to play on our outdoor sportsball teams sometimes seized during practice. If your insulation is up to snuff after the initial reduction of humidity if you don't have really leaky windows or cats that take forever to decide whether they want in or out or whatever then it's not that bad.

These figures are for 3,747 ft^2 of conditioned space across 2 floors with 8 tons of air conditioning, 4 per floor never exceeding 72 degrees unless well over 100f outside to reduce load on the grid I change to 78f. DisplayChart.png
IMG_20200415_013704.jpg
 
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GiGaBiTe

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You're doing it wrong, your central(!) air conditioning has a condensation drain tube that runs to the outdoors. There is no bucket to fill so long as that drain tube remains clear and is appropriately sized.
No, you're making hilariously incorrect assumptions on how my house is air conditioned. I don't need a lesson on how air conditioners work from you, thanks.

But do tell how my central AC needs a bigger drain to accommodate a window unit in my garage which is on a stand that drains into a bucket beneath it? You're talking willy wonka levels of insanity on that drain pipe. It exhausts into our heavily vented attic (gable, soffit and ridge), so don't worry your little brain about it eating its own exhaust. And considering I only run it for a few hours at a time, only while I'm in there, there's nothing to worry about.

You might want to look at a different insulation strategy or obtaining a more powerful central air conditioning system. Even your window units could use a drain tube, the buckets are for less humid places... Your house was built improperly for the location if it's HVAC system can't handle your weather.
Yeah, let me also tear down and rebuild my house while I'm at it, since it's nearly 40 years old and isn't up to modern building codes with fancy insulation used these days.

You don't have to sit under an air register, you can sit further away from them or you can use ceiling fans, desk fans, or standing fans (or a combination) to help spread the cool air around your office or wherever you lurk and keep your equipment.
Again, you're making hilariously incorrect assumptions about my house. I think I've lived in my house quite a bit longer than you have, and have a better idea of what will and won't work.

By the way, this thread is about computer memory, not the hit TV show "This Old House" hosted by Bob Villa.
 
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kirbyrj

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So I just did a search on this issue for X79 motherboards, and sure enough, I got a lot of hits. Since I'm now focused on my new build, I'm putting this item on my "to do sometime" list. :) Thanks for the suggestion.
I'm sure both x58 and x79 boards had similar issues with memory channels dropping out. Pretty much it's a pin issue in the socket IIRC.
 

Wade88

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No, you're making hilariously incorrect assumptions on how my house is air conditioned. I don't need a lesson on how air conditioners work from you, thanks.

But do tell how my central AC needs a bigger drain to accommodate a window unit in my garage which is on a stand that drains into a bucket beneath it? You're talking willy wonka levels of insanity on that drain pipe. It exhausts into our heavily vented attic (gable, soffit and ridge), so don't worry your little brain about it eating its own exhaust. And considering I only run it for a few hours at a time, only while I'm in there, there's nothing to worry about.



Yeah, let me also tear down and rebuild my house while I'm at it, since it's nearly 40 years old and isn't up to modern building codes with fancy insulation used these days.



Again, you're making hilariously incorrect assumptions about my house. I think I've lived in my house quite a bit longer than you have, and have a better idea of what will and won't work.

By the way, this thread is about computer memory, not the hit TV show "This Old House" hosted by Bob Villa.
Your crappy house is damaging your computers though...
 

GiGaBiTe

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I'm sure both x58 and x79 boards had similar issues with memory channels dropping out. Pretty much it's a pin issue in the socket IIRC.
The heavier air coolers seem to cause it more, especially if a stiff backplate isn't used. I've also seen it happen on the smaller LGA sockets, I have an 1150 board which is warped from a Hyper 212 Evo of all things and it's very temperamental on booting and not. I think it being shipped halfway across the country and back likely had something to do with it though.
 

x509

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I'm sure both x58 and x79 boards had similar issues with memory channels dropping out. Pretty much it's a pin issue in the socket IIRC.
Then unless I can somehow locate and actually fix the problem pins, this board is ready for the recycle bin. After I removed and re-installed the CPU, the board would not even boot, a sign of more pin problems.

On my new AMD x57o board, the pins are on the CPU, so it's super easy to get the CPU properly installed into the socket.

@GagaBiTe. This board has a Hyper 212, but with a metal backplate.
 

GiGaBiTe

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Then unless I can somehow locate and actually fix the problem pins, this board is ready for the recycle bin. After I removed and re-installed the CPU, the board would not even boot, a sign of more pin problems.

On my new AMD x57o board, the pins are on the CPU, so it's super easy to get the CPU properly installed into the socket.

@GagaBiTe. This board has a Hyper 212, but with a metal backplate.
Ship the board to me so I can see if I can fix it lol.
 

vick1000

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Sure, if you want to be a mummified popsicle with a huge electric bill. I have central air AND a window unit to assist in our hot summers, it's hard to get the humidity below 60%. I have another window unit in the garage that will fill a five gallon bucket in just a couple of hours.



Memtest most definitely stresses the memory controller, how do you think it writes so much data to every memory module so quickly? It is even more stressful in SMT mode where every core/thread is used to test memory.

Prime95 is not a valid method of testing memory, it is known to give false positives, especially in older versions of the software. And even if it does show a problem, it won't show you where it is and you're back to where you started. Memtest will tell you the exact location of the memory failure, and since the memory map is linear in most cases, it's super easy to figure out which stick is defective. Heck, you can use it to figure out which memory chip on which stick is defective.
Well I stopped using it because it was not finding anything wrong on several systems, and bad sticks were passing. Prime was throwing errors and/ or crashing on blend or large FFT, testing single sticks alone. Some memory is very power sensitive, and the power subsystem for the CPU and DIMM slots can cause out of spec flux when stressed. So Prime can find flux incompatability as well. I have never had Prime throw errors on a good stick that's compatible, and replacing the sticks Prime errors on, fixes the problem PC 100% for me, Memtest does not.
 

GiGaBiTe

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Well I stopped using it because it was not finding anything wrong on several systems, and bad sticks were passing.
How long were you running Memtest? I've never had it fail to detect a bad stick of RAM with a test of at least 8 hours. By that time, the memory has been considerably stressed and even weak memory that works fine when cold and only fails when stressed is found.

Some memory is very power sensitive
All memory is power sensitive, you don't give it enough juice and it will act erratically. This was especially true back in the DDR2 days with higher performance memory that sometimes required up to 2.3v to operate normally.

and the power subsystem for the CPU and DIMM slots can cause out of spec flux when stressed. So Prime can find flux incompatability as well.
Do enlighten me on what "flux incompatibility" is, I've never heard of the term outside of metallurgy.
 

vick1000

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How long were you running Memtest? I've never had it fail to detect a bad stick of RAM with a test of at least 8 hours. By that time, the memory has been considerably stressed and even weak memory that works fine when cold and only fails when stressed is found.



All memory is power sensitive, you don't give it enough juice and it will act erratically. This was especially true back in the DDR2 days with higher performance memory that sometimes required up to 2.3v to operate normally.



Do enlighten me on what "flux incompatibility" is, I've never heard of the term outside of metallurgy.
Memory transistors work by way of a flux in voltage, if the voltage is too high or low during write operations, it will throw errors. If a motherboard does not control the peaks and valleys correctly, it is considered incompatible with the DIMM. JEDEC tries to give specification guidlines, but there are many flaws in the system. Good quality modules have a pretty wide margin for flux, but a few sketchy components can push things out of spec. Flux is just a term for fluctuation. So if the power sub system is not stressed, you don't get real world testing.
 
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I have memory problems too , it seems to be a perennial problem that was never sorted out by the manufacturers . I am on my 4th x58 board . Recently the computer was running well with 4 x 2gb in triple channel . Then I got bored and tried ( again ) for the 6 x 2gb and everything went pear-shaped ! Now I am stuck on 4gb , was 6gb couple of days ago . I tried 2 processors cleaned slots sticks etc re-seated and still the same . I do not think it is a CPU pin issue , though i did have some success - before - with aplying some pressure to the cpu heatsink before the bios screen . I think this will be my last board , probably go for the Chinese x79 boards next .
 

kirbyrj

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I have memory problems too , it seems to be a perennial problem that was never sorted out by the manufacturers . I am on my 4th x58 board . Recently the computer was running well with 4 x 2gb in triple channel . Then I got bored and tried ( again ) for the 6 x 2gb and everything went pear-shaped ! Now I am stuck on 4gb , was 6gb couple of days ago . I tried 2 processors cleaned slots sticks etc re-seated and still the same . I do not think it is a CPU pin issue , though i did have some success - before - with aplying some pressure to the cpu heatsink before the bios screen . I think this will be my last board , probably go for the Chinese x79 boards next .
If you can get memory to work by applying pressure to the heatsink, I'd say it's almost definitely a CPU pin issue.

That being said, you'd probably get more mileage out of a chinese x79 board at this point.
 

x509

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If you can get memory to work by applying pressure to the heatsink, I'd say it's almost definitely a CPU pin issue.

That being said, you'd probably get more mileage out of a chinese x79 board at this point.
Well I recently upgraded to an AMD x570 board with 3900x CPU and I'm very happy with the setup. However, there is still value in the Intel 3930K CPU and 32 GB of memory, but I don't want to burn out my aging eyes trying to fix CPU pins. Any suggestions for a Chinese x79 board? I have always wanted to home-build a NAS.
 

kirbyrj

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Well I recently upgraded to an AMD x570 board with 3900x CPU and I'm very happy with the setup. However, there is still value in the Intel 3930K CPU and 32 GB of memory, but I don't want to burn out my aging eyes trying to fix CPU pins. Any suggestions for a Chinese x79 board? I have always wanted to home-build a NAS.
There's a guy in the FS section selling one for like $90 shipped (IIRC). I think it was called the "X79 Plex Turbo" and he had them paired with the 10 Core Xeons.
 
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If you can get memory to work by applying pressure to the heatsink, I'd say it's almost definitely a CPU pin issue.

That being said, you'd probably get more mileage out of a chinese x79 board at this point.
I have a little query . Now I have been trying to update the BIOS , ATM it is updated to F5 from F4 But memory is stuck on 4 gb for both F4 and F5 . Now everyone will say that is is the Dimm slots or the CPU socket , naturally . The thing is the F6 bios lets the BIOS see all installed memory - 8GB in this case ( I may have a single defective memory module that would prevent 12gb showing ) . The problem is , for me anyway , that I cannot get the computer past the starting windows logo where it hangs . I have not tried the F7 or F8 Bios yet , as they are beta . So in this instance it is the bios that is stopping all memory from being used , though the previous bios - some time ago did use all 12 gb
 

cyclone3d

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Huh.. the only time I have ever had problems with x58 or x79 systems not detecting all the RAM was:

1. CPU needed to be reseated.
2. CPU contact pads had become oxidized and needed to be cleaned.... pencil eraser or deoxit will work fine for this
3. Bent socket pins.... fairly easy to fix unless you have absolutely mangled them.
4. RAM not seated all the way or needed to be reseated
5. Edge connector on RAM has become oxidized... see #2.

I've been running x58 and x79 platforms since they were new and have only ever had 1 board die and I am unsure if it was the CPU that took out the board or if it was the board that took out the CPU.

I really never understood all the problems that people seem to have with these platforms.
 
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