Question Asus Prime z790a RAM issues

[Karrken]

New build. Asus Prime z790a wifi mobo, i7 13700k, Trident z5 6000 36-36-36-96 ddr5 ram (4x16), Zotac 3090ti, Thunderbolt card, Sound blaster ae5, Ryujin 2 240 AIO, EVGA 1300 psu

When I put ram in slots 2 and 4, system works great. When I add ram in slots 1 and 3, won't even POST. No video output at all. I've tried every combination and all 4 sticks are solid, it's just something about slots 1 and 3.

Asus support says the CL36 isn't on the QVL, but CL40 is. Could this be the issue?

 

[Darkbreeze]

Could this be the issue?

Not really, because at the default configuration which is what you'd have on initial boot before you set up the XMP profile, it's not going to be that tight anyhow. This seems a lot more like bent pins in the CPU socket to me if all the RAM works properly in A2 and B2 but won't POST with the same memory when you try to populate A1 and B1. Or, if there are no bent pins on the CPU socket then it could certainly just be a motherboard issue or even something wrong with the CPU. CPU failures are rare, but they do happen.

 

[Karrken]

Not really, because at the default configuration which is what you'd have on initial boot before you set up the XMP profile, it's not going to be that tight anyhow. This seems a lot more like bent pins in the CPU socket to me if all the RAM works properly in A2 and B2 but won't POST with the same memory when you try to populate A1 and B1. Or, if there are no bent pins on the CPU socket then it could certainly just be a motherboard issue or even something wrong with the CPU. CPU failures are rare, but they do happen.

Thanks. Any advice on determining the culprit? I'll check the pins and see if there is any visible damage. Just realized I didn't list the chip (updated now). It's a i7 13700k. How can I confirm if it's a mobo issue? I'd hate to RMA the mobo unless I have to.

 

[Darkbreeze]

How To - Motherboard bench testing

Finding the problem through bench testing If you are here then it’s likely you have encountered a serious hardware issue and have been unable to resolve it using the standard no-POST troubleshooting procedures. If you have not yet attempted to resolve your issues using the no-POST...

forums.tomshardware.com

 

[Karrken]

So after extensive trials, the fix appears to be adding a second 8-pin to the mobo. All 4 sticks are working fine now. No other changes were made. It's possible the ram wasn't seated proper initially, but does seem unlikely considering the number of times it was removed and reseated in testing.

 

[Darkbreeze]

So, you didn't have all the EPS connectors plugged in?

Using all of the EPS connectors is starting to become a necessity rather than a "only if overclocking" due to the very high TDP of the latest Gen processors. With four DIMMs installed you might also want to consider adding a small amount of additional DRAM voltage if you encounter any errors or problems now that it is at least POSTing with the extra power plugged in. I'd also recommend running Memtest86 to make sure there are no fundamental problems.

Memtest86​

Go to the Passmark software website and download the USB Memtest86 free version. You can do the optical disk version too if for some reason you cannot use a bootable USB flash drive.


Create bootable media using the downloaded Memtest86. Once you have done that, go into your BIOS and configure the system to boot to the USB drive that contains the Memtest86 USB media or the optical drive if using that option.


You CAN use Memtest86+, as they've recently updated the program after MANY years of no updates, but for the purpose of this guide I recommend using the Passmark version as this is a tried and true utility while I've not had the opportunity to investigate the reliability of the latest 86+ release as compared to Memtest86. Possibly, consider using Memtest86+ as simply a secondary test to Memtest86, much as Windows memory diagnostic utility and Prime95 Blend or custom modes can be used for a second opinion utility.

Click here to download Memtest86 USB package​

Create a bootable USB Flash drive:

1. Download the Windows MemTest86 USB image.

2. Right click on the downloaded file and select the "Extract to Here" option. This places the USB image and imaging tool into the current folder.

3. Run the included imageUSB tool, it should already have the image file selected and you just need to choose which connected USB drive to turn into a bootable drive. Note that this will erase all data on the drive.


No memory should ever fail to pass Memtest86 when it is at the default configuration that the system sets it at when you start out or do a clear CMOS by removing the CMOS battery for five minutes.

Best method for testing memory is to first run four passes of Memtest86, all 11 tests, WITH the memory at the default configuration. This should be done BEFORE setting the memory to the XMP profile settings. The paid version has 13 tests but the free version only has tests 1-10 and test 13. So run full passes of all 11 tests. Be sure to download the latest version of Memtest86. Memtest86+ has not been updated in MANY years. It is NO-WISE as good as regular Memtest86 from Passmark software.

If there are ANY errors, at all, then the memory configuration is not stable. Bumping the DRAM voltage up slightly may resolve that OR you may need to make adjustments to the primary timings. There are very few secondary or tertiary timings that should be altered. I can tell you about those if you are trying to tighten your memory timings.

If you cannot pass Memtest86 with the memory at the XMP configuration settings then I would recommend restoring the memory to the default JEDEC SPD of 1333/2133mhz (Depending on your platform and memory type) with everything left on the auto/default configuration and running Memtest86 over again. If it completes the four full passes without error you can try again with the XMP settings but first try bumping the DRAM voltage up once again by whatever small increment the motherboard will allow you to increase it by. If it passes, great, move on to the Prime95 testing.

If it still fails, try once again bumping the voltage if you are still within the maximum allowable voltage for your memory type and test again. If it still fails, you are likely going to need more advanced help with configuring your primary timings and should return the memory to the default configuration until you can sort it out.

If the memory will not pass Memtest86 for four passes when it IS at the stock default non-XMP configuration, even after a minor bump in voltage, then there is likely something physically wrong with one or more of the memory modules and I'd recommend running Memtest on each individual module, separately, to determine which module is causing the issue. If you find a single module that is faulty you should contact the seller or the memory manufacturer and have them replace the memory as a SET. Memory comes matched for a reason as I made clear earlier and if you let them replace only one module rather than the entire set you are back to using unmatched memory which is an open door for problems with incompatible memory.

Be aware that you SHOULD run Memtest86 to test the memory at the default, non-XMP, non-custom profile settings BEFORE ever making any changes to the memory configuration so that you will know if the problem is a setting or is a physical problem with the memory.

 

[Karrken]

Update: both EPS utilized now. System was very unstable. Disabling XMP in BIOS has stabilized everything apparently. After diving deeper looks like the motherboard is very very specific about the RAM it likes. The 7000 didn't work well, but 7200 is listed on the QVL. Looks like restricting it to 4800 is working, just makes for some expensive 4800 RAM.

 

[Darkbreeze]

If it works at lower speeds you can likely at the least get closer to your XMP if not entirely at your XMP by bumping the DRAM voltage. I'd start by enabling XMP but increase the DRAM voltage by .005v or whatever the lowest increment it will allow you to increase it above 1.35v is, then save settings and restart. If it's still unstable, increase the DRAM voltage again by the lowest increment the BIOS will allow in the advanced memory section and save settings/restart. If it's not stable by the time you get to 1.4v then drop the DRAM frequency down by whatever the next lowest common speed is, and start over at 1.35v DRAM voltage.

So, if the memory speed is (For example) 7600 and it won't run stable at that speed by the time you get to 1.4v DRAM voltage, then drop down to 7200 and 1.35v. If still not stable, bump DRAM voltage again and try. If still no love by the time you get to 1.4v, drop to the next lowest DRAM frequency of 7000, again, just as an example. Your speed may be different, IDK, because first you say 6000mhz in the OP and here you've said 7000/7200. Whatever it is, that's basically the process. Even if you end up with 5400mhz at something between 1.35v and 1.4v it would be better than 4800mhz.

 

[Karrken]

If it works at lower speeds you can likely at the least get closer to your XMP if not entirely at your XMP by bumping the DRAM voltage. I'd start by enabling XMP but increase the DRAM voltage by .005v or whatever the lowest increment it will allow you to increase it above 1.35v is, then save settings and restart. If it's still unstable, increase the DRAM voltage again by the lowest increment the BIOS will allow in the advanced memory section and save settings/restart. If it's not stable by the time you get to 1.4v then drop the DRAM frequency down by whatever the next lowest common speed is, and start over at 1.35v DRAM voltage.

So, if the memory speed is (For example) 7600 and it won't run stable at that speed by the time you get to 1.4v DRAM voltage, then drop down to 7200 and 1.35v. If still not stable, bump DRAM voltage again and try. If still no love by the time you get to 1.4v, drop to the next lowest DRAM frequency of 7000, again, just as an example. Your speed may be different, IDK, because first you say 6000mhz in the OP and here you've said 7000/7200. Whatever it is, that's basically the process. Even if you end up with 5400mhz at something between 1.35v and 1.4v it would be better than 4800mhz.

Thanks, I'll give it a try. I typo'd my last response. The RAM is 6000 speed. I very much appreciate your in depth reply.

 

[Darkbreeze]

Good luck.

Reading this, the whole thing, might offer some further insights as well, possibly. Good information to know anyhow and it's basically written in mostly layman's terms so it's easily digestible.

How To - Troubleshooting problems with PC memory (RAM) and XMP profile configurations

In the beginning, there was......BIOS Before you go ANY further, go to the manufacturer product page for your specific motherboard model AND revision. Revision is an important aspect because for any given motherboard there may be more than one version of that model which will be identified...

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