PRIME Z690-A issue with RAM

[Ontis]

Greetings.

I am using a PC (preassembled by a local vendor) based on Z690-A motherboard with 12900KF CPU. This PC originally came with 2x 16Gb RAM from G.Skill manufacturer labeled as F5-6000U4040E16GX2-TZ5RK, but I toned it down to 4800 MHz.

After about two years of using I've got myself a spare Kingston Fury DDR5-6000 32768MB PC5-48000 2Rx8 (KF560C40BB-32) RAM module. I decided to give it a try and slotted into B1 slot with two old RAM modules occupying A1 and A2.

The PC made it to POST and BIOS, but after I quit the BIOS shell it simply never started working again. The motherboard had its "DRAM" LED permanently orange with it sometimes switching to red for a short duration and then back to orange.

Afterwards I removed my old 2x16 Gb RAM modules and checked if I can start up with just the new Kingston RAM module.

The situation was exactly same: I made it through POST, entered BIOS, double-checked everything to be set to 'Auto' and then rebooted.

The PC refused to start up again.

Now I have several questions:

1. Is this specific new RAM module somehow incompatible with my motherboard?

2. I have an opportunity to get myself two more RAM modules of the exactly same model as my original ones. Will I be able to run 4 of 16 Gb G.Skill modules on this motherboard?

[Ontis]

But it WORKS PROPERLY on a PC build around MSI PRO Z690, and so does the 32GB Kingston single RAM module!

I've been told to "update BIOS just in case" recently. How do I do that properly in order to avoid any mistakes? My motherboard is PRIME Z690-A.

[achugh]

Hi @Ontis I am sorry to hear about your troubles. I noticed the following comment from you.

I did exactly that. After the PC refused to load with my old RAM placed in A1+A2 and new RAM placed in B1+B2 I removed my old RAM and switched the new 2x16 GB modules to be mounted in A2+B2 slots instead.

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If you check your board's manual, the sticks should go into A2/B2 and A1/B1. In other words, can you try the following:

1. Install your older sticks into A2 and B2 slot.
2. Go into BIOS and set your memory to AUTO. Do not set to any manual entry yet.
3. Performa full Windows boot to confirm that everything is good.
4. Now install your new memory stick in A1 and B1. You can make sure you are pairing the sticks correctly using the SERIAL NUMBERS on the sticks so you don't mix the old and new sticks.

I hope this may get you to enter into BIOS and complete your POST. Once you get into BIOS you can check your JEDEC values and XMP Profiles on the stick. Using this information you can try to find a happy medium.

If everything boots with AUTO using the A2/B2 (Old) + A1/B1 (New) combination then I would set the memory to XMP II profile and then use the speed as the delimiter. You can find more about it in the YouTube video mentioned in the comment of https://rog-forum.asus.com/t5/technologies-explained/memory-kits-overclocking-and-what-you-may-not-k... post.

The above post will explain why mixing kits is not recommended and so does this YouTube video. At lower speeds you may get lucky to make them work. It may not be 4800 MT/s. It might be even lower.

I hope this information helps your resolve your issue.