Question My ignorance of RAM has bitten me - where did I go wrong?

[kranky]

I built a new PC. First one in 10+ years, so I had to try to catch up on current tech. I bought 2x16GB DDR5-6000 RAM. System started up fine. Decided I wanted 64GB instead, so I bought 2x32GB RAM. I saw that other people had used DDR5-6000RAM with 2x32GB RAM with the same ASUS Prime Z790-A motherboard and I5-12600K CPU.

Well the 2x32GB RAM won't even get through the UEFI startup. An LED on the motherboard lights up "DRAM" which only indicates there's an error with DRAM.

So not all DDR5-6000 2x32GB is equal, I guess? The RAM I got is TeamGroup T-Create DDR5-6000 (2Rx8) CL 34-44-44-84 1.3V. Is there something I overlooked to be able to find usable 2x32GB RAM kits? DDR5-6000 in a 2x32GB config works for some people but I don't know what to look for. Is the "QVL" list an absolute must? I thought it could be used as a guide (in other words, if multiple 2x32GB DDR5-6000 kits work, others will work too even if not specifically listed). The kit I bought is not explicitly listed on the QVL. And if there's something I can to do adjust some setting to improve my chances of it working, I'm all ears.

 

[fralexandr]

Have you updated the bios?
V1020 (6-15-23) improved memory compatibility

PRIME Z790-A WIFI｜Motherboards｜ASUS USA

ASUS Prime Z790-A WIFI, an Intel Z790 LGA 1700 ATX motherboard with PCIe® 5.0, four M.2 slots, 16+1 DrMOS, DDR5, Intel WIFI 6E, 2.5 Gb LAN, HDMI®, DP, USB 3.2 Gen 2x2 Type-C®, front USB 3.2 Gen 2 Type-C®, Thunderbolt™ (USB4®) support

www.asus.com

 

[Tech Junky]

RAM is RAM in most cases. DDR5 has some quirks and the first boot being one of them. Some boards if not all will require a training period up to 10 minutes depending on how much RAM is installed.

QVL is just what they tested not a must.

https://pcpartpicker.com/list/cT9W2m

I plopped your components you listed into the system and there's no apparent issue with that combo. So, looking at the MOBO would be my next idea.

Looking at the MOBO specs up to 5600 w/o an OC / XMP profile configure should work.

Looking at the manual....

https://dlcdnets.asus.com/pub/ASUS/mb/LGA1700/PRIME%20Z790-A%20WIFI/E21270_PRIME_Z790-A_WIFI_UM_V3_WEB.pdf?model=PRIME%20Z790-A%20WIFI

'
Asus tends to do some weird stuff IME but, then again it could be Intel to blame as well on some of it. Why there's an error light w/o a decoder ring though doesn't make much sense.

 

[igor_kavinski]

Yup. Give it 10 minutes.

 

[BonzaiDuck]

I'm still debating whether I want to build a new one, or just buy a new one. I started my "crisis" thread the other day, because my server seemed to be malfunctioning -- all explained in my thread.

That's the situation that costs more but with more benefits -- building your own. I haven't bought an OEM system, as I said elsewhere, since 1994. One tends to pick good parts. We were "over-clocking" five years ago or earlier, when I built my Skylake system. So I would pick upper-tier RAM -- not particularly the fastest OC RAM, but in a choice of G.SKILL models, I'd opt for Trident-Z.

I myself would've picked an ASUS motherboard. But whatever the make and model, I have this advice about "QVL". For a particular make or manufacture -- say, G.SKILL -- first find reference to any similar models you are considering in the QVL list. If it's just a matter of DDR speed, and you find a similar product that's faster, the appearance of the lesser models in the QVL list should tell you something. With the RAM which I've eventually purchased for a computer-build, these indications didn't fail me.

But it is essential to match the motherboard and the RAM. They either work together, or they don't.

For the ASUS motherboard, earlier products i remember may have required pushing the "Mem-OK" button to initially configure the RAM. Usually, though, it would simply configure to the Intel default speed, and you would then increase the speed to the "OC" spec after initially testing the RAM at the Intel default for the motherboard and chipset.

 

[kranky]

Thank you guys for the inputs. Yes I have the BIOS updated to V1020. @Tech Junky , can you explain the "wait 10 minutes" thing? Right now I don't yet have an OS installed. I can power up and get into the BIOS. The 2x32 6000 RAM isn't even detected on power-up. The 2x16 RAM gets me into the BIOS. What would I be looking for when waiting 10 minutes if I try the 2x32 kit again?

 

[Tech Junky]

DDR5 requires a training period before it will POST.

 

[BonzaiDuck]

DDR5 requires a training period before it will POST.

All news to me -- and I'm wondering if I'm going to build any more machines myself, as I said earlier. Extra time and trouble when I don't have much extra time . . .

 

[Tech Junky]

DDR5 systems may require training

A small number of DDR5 systems and motherboards require a period of "training" newly installed memory to work with the system and allow access to the UEFI, or otherwise to complete the system's power-on self-test (POST).

www.crucial.com

 

[Justinus]

Did you reset the CMOS after swapping ram? I have had issues even with UEFI at defaults when swapping DDR5 kits before on AM5, I'm guessing because it tries to initialize with the training from the previous kit or something goes wrong.

Doing a CMOS reset after swapping in the new kit and letting it fully initialize and train the new ram fixed it in my cases.

 

[BonzaiDuck]

Did you reset the CMOS after swapping ram? I have had issues even with UEFI at defaults when swapping DDR5 kits before on AM5, I'm guessing because it tries to initialize with the training from the previous kit or something goes wrong.

Doing a CMOS reset after swapping in the new kit and letting it fully initialize and train the new ram fixed it in my cases.

I think that's always preferable. If DDR5 RAM is designated as "OC" RAM and there is a default Intel DDR speed, you'd want it initially set to default before setting the XMP profile. I assume they still have "XMP" profiles under DDR5?

 

[igor_kavinski]

I assume they still have "XMP" profiles under DDR5?

They do. But be careful if you are buying DDR5. There are some cheap kits out there that only support EXPO (AMD's version of XMP). I have such a kit. It works at 5600 on AM5 but on my Z790, I can't get it beyond 4600.

 

[igor_kavinski]

What would I be looking for when waiting 10 minutes if I try the 2x32 kit again?

I think you should try Justinus's suggestion of clearing the CMOS and then trying the 64GB kit. After hitting the power switch, if the DRAM light comes up, ignore it and give your mobo at least 10 minutes to POST.

You may want to test with just one DIMM installed first.