[SOLVED] Single Channel and Dual Channel RAM Problem

Status
Not open for further replies.
May 26, 2019
14
1
10
I recently built a new computer and I noticed that when running a single stick of ddr4-3000 corsair ram my bios showed a speed of 2133mhz and the respective amount in CPU-Z. However, when I installed the other stick of Ram from the package the speed dropped to 800mhz in bios and 400 in CPU-Z. Not sure what could cause this problem or how to fix it please help.

Motherboard: MSI Z390-A Pro
Ram: DDR4-3000 Corsair Vengeance LPX 2x8gbs
GPU: GTX 1660ti
CPU: i5-9600k

I tested the a set of 2x8gbs of the ddr4-2400 memory that I have in the computer I built a couple years ago and the same thing happened.
I also tried to manually set the ram speeds and turning on xmp but that led to the computer not being able to boot properly.
Both sticks of Ram work individually and are able to run at 2133mhz on their own and boot the computer.
 
Solution
I mean, that's your call. If the motherboard doesn't allow the memory to work in dual channel, then there is a problem. There is no argument to made there. And there is nothing, no software, nothing, that could cause that. ONLY the CPU, motherboard and memory could cause that problem unless like I said there is either a bent pin on the motherboard (Still a motherboard issue) or the CPU cooler is installed incorrectly with one side or corner being tighter than the others because the backplate is unevenly tightened or the mounting hardware is. That can cause the CPU to sit "cocked" in the socket, which can either cause pins to short or not make contact, in which case SOMETHING has to not work because the majority of pins are there for a...
Make sure you are installing them in the correct slots, which are the A2 and B2 slots (Designated as DDR4_1 and DDR4_2 on some boards). Those are the 2nd and 4th slots over from the CPU socket going towards the edge of the motherboard.

UB6JJIp.png


It would be VERY wise to check for any BIOS updates on the motherboard product page and if there ARE any which are newer than what you have currently installed, that you update to the latest one. There are several incremental BIOS updates for your board that explicitly address memory compatibility, but you need only install the latest one to get all prior updates.
 
Last edited:
May 26, 2019
14
1
10
Make sure you are installing them in the correct slots, which are the A2 and B2 slots (Designated as DDR4_1 and DDR4_2 on some boards). Those are the 2nd and 4th slots over from the CPU socket going towards the edge of the motherboard.

UB6JJIp.png


It would be VERY wise to check for any BIOS updates on the motherboard product page and if there ARE any which are newer than what you have currently installed, that you update to the latest one. There are several incremental BIOS updates for your board that explicitly address memory compatibility, but you need only install the latest one to get all prior updates.
This is my second computer that I've built and the on that I have works absolutely fine. I have the ram installed into the right positions and made sure that I updated the bios to the newest version. I'm just not really sure what to do at this point I ran a benchmark and it said that the ram is under-performing by a lot. I'm considering just returning the set of ram and getting a single stick of 16gb ddr4 because I bought the parts very recently and I haven't seen anyone else that has this problem so it's hard for me to find a solution. I guess it's possible that it's a problem on the motherboard but I would hate to have to go through the hassle of uninstalling all the parts and repackaging the motherboard because everything is working fine other than this one problem. The computer boots fine and everything works it's just that in games I can tell that the memory is lacking because it's clocked out at 800mhz. When I play on just one stick of RAM the performance is almost similar if not better than when I have two sticks of RAM in.
 
Last edited by a moderator:
You don't want to do that. Single stick has half the bandwidth of a dual stick dual channel configuration.

If there is a motherboard issue that is inherently causing dual channel or memory performance in general to not work as expected, then there are bigger problems that need to be addressed. Trying to use just one stick is like using a temporary tire on your car. Yeah, it will get you a short distance, but beyond that it's not a wise idea to continue on that way.

With both sticks installed in the A2 and B2 slots, download HWinfo, install it, open it, choose the "Sensors only" option and then scroll down to the memory sensor readings. See what HWinfo is reporting on memory speed.

Should look something like this section. Keep in mind, that reported memory speed is USUALLY HALF of actual speed, because memory is DDR, double data rate, which means that it will actually be running at twice what is shown. It may be that CPU-Z is wrong. Some utilities report sensor data incorrectly, often.


14l39mw.jpg
 
May 26, 2019
14
1
10
You don't want to do that. Single stick has half the bandwidth of a dual stick dual channel configuration.

If there is a motherboard issue that is inherently causing dual channel or memory performance in general to not work as expected, then there are bigger problems that need to be addressed. Trying to use just one stick is like using a temporary tire on your car. Yeah, it will get you a short distance, but beyond that it's not a wise idea to continue on that way.

With both sticks installed in the A2 and B2 slots, download HWinfo, install it, open it, choose the "Sensors only" option and then scroll down to the memory sensor readings. See what HWinfo is reporting on memory speed.

Should look something like this section. Keep in mind, that reported memory speed is USUALLY HALF of actual speed, because memory is DDR, double data rate, which means that it will actually be running at twice what is shown. It may be that CPU-Z is wrong. Some utilities report sensor data incorrectly, often.


14l39mw.jpg
I’ll try another benchmark for sure the only problem I can see with that is when I booted up the computer with one stick of ram in my bios it ran the ram at the right speed but when I run dual channel in my bios it says the ram is running at 800mhz and that’s confirmed from CPU-Z as well. I’ll send some screenshots when I get a chance. I really appreciate your help and if you can help me figure this out that would be great. I’m aware that the mhz is doubled but in CPU-Z it says it was running at 400mhz confirming that it’s only running at 800mhz. This is also reflected in the fact that the frame rates of the games are underperforming as well.
 
May 26, 2019
14
1
10
I’ll try another benchmark for sure the only problem I can see with that is when I booted up the computer with one stick of ram in my bios it ran the ram at the right speed but when I run dual channel in my bios it says the ram is running at 800mhz and that’s confirmed from CPU-Z as well. I’ll send some screenshots when I get a chance. I really appreciate your help and if you can help me figure this out that would be great. I’m aware that the mhz is doubled but in CPU-Z it says it was running at 400mhz confirming that it’s only running at 800mhz. This is also reflected in the fact that the frame rates of the games are underperforming as well.
The most irritating part is that even when I try to set the ram to work at the proper mhz it won’t boot and tells me that my overclock settings didn’t work and reverts back to default. From what I’m telling you are you thinking this is a motherboard issue?
 
So, I'd try this. Do a hard reset of the BIOS, and then after restarting, go back in and set the XMP profile. Then save settings and reboot.

Hard Reset of BIOS instructions.

Power off the unit, switch the PSU off and unplug the PSU cord from either the wall or the power supply.

Remove the motherboard CMOS battery for five minutes. During that five minutes, press the power button on the case for 30 seconds. After the five minutes is up, reinstall the CMOS battery making sure to insert it with the correct side up just as it came out.

Install your two memory modules making SURE they are in the A2 and B2 slots. ONLY. Don't assume you know where they belong. Simply install them in the second and fourth slots away from the CPU socket.

Now, plug the power supply cable back in, switch the PSU back on and power up the system. It should display the POST screen and the options to enter CMOS/BIOS setup. Enter the bios setup program and reconfigure the boot settings for either the Windows boot manager or for legacy systems, the drive your OS is installed on if necessary.

Save settings and exit. If the system will POST and boot then you can move forward from there including going back into the bios and configuring any other custom settings you may need to configure such as Memory XMP profile settings, custom fan profile settings or other specific settings you may have previously had configured that were wiped out by resetting the CMOS.
 
May 26, 2019
14
1
10
BTW, you DID purchase both those memory modules TOGETHER, in a kit, right? You didn't get them one at a time, whether they are the same model or not?
Yes I obviously purchased them in a kit and I know how to install memory so I know that they were in the proper slots when I installed them. Is there any possibility removing the CMOS battery will ruin the motherboard. This may seem like a dumb question I’m not sure you said “if the system will Post” making me somewhat worried that there’s a possibility that it will not post. I’ve never ran into the problem of having to do that before so that’s the only reason I’m asking.
 
May 26, 2019
14
1
10
The thing that is throwing me off is the fact that the memory is working fine in dual channel but it’s just running at a low mhz. I don’t think it’s a problem with the ram either because both sticks run at the right mhz in single channel individually and when I plugged in a different set of ram the same problem happened even though I know the ram works properly in my other computer.
 
May 26, 2019
14
1
10
BTW, you DID purchase both those memory modules TOGETHER, in a kit, right? You didn't get them one at a time, whether they are the same model or not?
If you could please read my new msg's and let me know what you think that would be really appreciated because I asked a lot of questions that I hope you might have the answers to.
 
May 26, 2019
14
1
10
Try both sticks individually in the B2 slot. See what happens. Curious if there is maybe just a problem with that slot, indicating a bad motherboard.
I tried both sticks of ram in both the A2 and B2 slots individually and everything worked just fine. I actually have a single stick of ram running in the B2 slot right now running xmp at 3000mhz there are only problems when I try to run dual channel.

I am also trying to post pictures of the cpu-z into this thread but I am getting messages saying that I cannot post because of spam or inappropriate content
 
Then I would first remove the CPU and check for proper installation or bent pins. The internal memory controller that handles the memory operations is located inside the CPU and if there is even a minutely bent pin on the motherboard it can affect anything from PCI lanes to storage to memory operations. It would be very possible for single sticks to work fine but dual channel to not work, or any number of possible glitches, with even one slightly bent pin.

If there are no bent pins at all and nothing looks burnt or discolored on the motherboard or CPU electrical contacts, then I would RMA the motherboard or return it for replacement.
 
May 26, 2019
14
1
10
Then I would first remove the CPU and check for proper installation or bent pins. The internal memory controller that handles the memory operations is located inside the CPU and if there is even a minutely bent pin on the motherboard it can affect anything from PCI lanes to storage to memory operations. It would be very possible for single sticks to work fine but dual channel to not work, or any number of possible glitches, with even one slightly bent pin.

If there are no bent pins at all and nothing looks burnt or discolored on the motherboard or CPU electrical contacts, then I would RMA the motherboard or return it for replacement.

Before I do that I want to provide you with some more information so let me know what you think. I tested both of the ram sticks in the B2 slots and both were able to run at 3000mhz in xmp mode but when I tested both sticks of ram in the A2 slot I was presented with a message that the overclock settings were unable to be applied and that the default settings were reapplied. Both of the sticks of ram were running at 2133mhz but when I tried to apply xmp to raise the mhz neither stick was able to do so. Are you thinking I should still check my cpu for bent pins or does this sound like it's the motherboard's fault?
 
Either way it would be a motherboard problem, but you need to know if it's just a faulty board or a bent pin, because if it's a bent pin then that is not warrantable, but it MIGHT be fixable. Bent pins can sometimes be straightened, but they are pretty much always the fault of the user unless you notice that it is that way BEFORE you install the CPU.
 
May 26, 2019
14
1
10
Either way it would be a motherboard problem, but you need to know if it's just a faulty board or a bent pin, because if it's a bent pin then that is not warrantable, but it MIGHT be fixable. Bent pins can sometimes be straightened, but they are pretty much always the fault of the user unless you notice that it is that way BEFORE you install the CPU.
Would you recommend that I attempt to restart the cmos first before I take the cpu out for inspection because I noticed that someone else was having the exact same problem as me with almost the exact same parts so I would assume that it's more likely for it to be a software issue if more than one person is having the issue at about the same time. Thank you so much for you advice and help btw I know I am asking a lot of questions but I really do appreciate you helping me out.

I'm just having trouble believing that one of the pins on the cpu is bent because everything runs fine on the cpu and I know that I installed it with a lot of care. I would hate for me to take the cpu out and then ruin something in the process of me taking it out because installing the cpu fan is a pain in the ass.

I am going to attempt a cmos restart as soon as possible but I'm waiting to get a jumper rather than taking out the battery because that is what my motherboard's manual recommends. I will keep you posted on what happens but for now I'm just going to let my little brother play with his computer on the single overclocked 8gb piece of ram as it works fine and runs the games he wants at max frames.
 
I mean, that's your call. If the motherboard doesn't allow the memory to work in dual channel, then there is a problem. There is no argument to made there. And there is nothing, no software, nothing, that could cause that. ONLY the CPU, motherboard and memory could cause that problem unless like I said there is either a bent pin on the motherboard (Still a motherboard issue) or the CPU cooler is installed incorrectly with one side or corner being tighter than the others because the backplate is unevenly tightened or the mounting hardware is. That can cause the CPU to sit "cocked" in the socket, which can either cause pins to short or not make contact, in which case SOMETHING has to not work because the majority of pins are there for a specific reason although there are some present for redundancy in some cases.

That's it. Incorrectly installed CPU or cooler, motherboard, memory or faulty CPU. Those are the ONLY things other than a bad BIOS firmware version that could cause a lack of dual channel operation and if it was the BIOS firmware then every system with that firmware version would have the same problem. Every one.

Windows or other software have nothing whatsoever to do with whether or not the memory runs at a given speed or runs in dual channel. That is all up to hardware and the BIOS UEFI firmware.
 
Solution
May 26, 2019
14
1
10
I mean, that's your call. If the motherboard doesn't allow the memory to work in dual channel, then there is a problem. There is no argument to made there. And there is nothing, no software, nothing, that could cause that. ONLY the CPU, motherboard and memory could cause that problem unless like I said there is either a bent pin on the motherboard (Still a motherboard issue) or the CPU cooler is installed incorrectly with one side or corner being tighter than the others because the backplate is unevenly tightened or the mounting hardware is. That can cause the CPU to sit "cocked" in the socket, which can either cause pins to short or not make contact, in which case SOMETHING has to not work because the majority of pins are there for a specific reason although there are some present for redundancy in some cases.

That's it. Incorrectly installed CPU or cooler, motherboard, memory or faulty CPU. Those are the ONLY things other than a bad BIOS firmware version that could cause a lack of dual channel operation and if it was the BIOS firmware then every system with that firmware version would have the same problem. Every one.

Windows or other software have nothing whatsoever to do with whether or not the memory runs at a given speed or runs in dual channel. That is all up to hardware and the BIOS UEFI firmware.
DARKBREEZE I ABSOLUTELY LOVE YOU!!!!!! I checked the cpu and none of the pins were bent, but then I checked the cpu cooler and noticed that I missed a step in the installation process where I neglected to put these small black casings around the screws. I took the cpu cooler off and the backplate, I reinstalled the cpu cooler correctly and I booted up the pc with the ram now running at 3000mhz in dual channel. You are an absolute life saver and I am so happy that you mentioned the CPU cooler because without you mentioning it I would have never even checked. God Bless!!!!1
 
  • Like
Reactions: mertiko95
Status
Not open for further replies.