Z790A WiFi - Help with Memories - Badly Needed

[DannyETH]

Hi everybody,

I have a Z790A WiFi motherboard with

Intel Core i9-13900KF Socket 1700 Box
Asus GeForce RTX 3060 12GB GDDR6
Asus ROG THOR 1000P2 Gaming 1000 W

I have 2 kits of Kingston KF556C40BBAK2-64 (4 x 32GB DDR5 5600 DIMMs) as I want to have 128 GB RAM.
These memories are listed as compatible with this MB on Asus compatibility chart.
I literally cannot make the system to work and/or install Windows 10. 
I tried to use XMP1 and XMP2 profiles, nothing works, I keep getting errors. Bios is updated to the latest version. I even tried to leave Auto setting in AI Tweaker and change only the memory speed in Dram Frequency field.

I also tried XMP1 and XMP2 profiles with lower frequencies, this did not work either, still got errors and BSODs in Windows 10 setup.

The ONLY way it seems to work is if I leave only two 32GB DIMMs in the motherboard with Ai Tweaker on Auto and it works at 4000MHz, but obviously this is not a solution.

Any help will be GREATLY appreciated, thanks in advance!

[JohnAb]

Somebody will correct me if I'm wrong, but your motherboard only supports max 2 sticks of that RAM, not 4. This is indicated by 1,2 in the right column. If 4 are supported, you will see 1,2,4.  

[DannyETH]

I just checked the memory compatibility page for the MB. Absolutely all supported memories are labeled socket 1,2, not even one of them has 1,2,4. And the motherboard, based on manufacturer specifications, is capable to support 192MB RAM so at least some of the supported memory types should have had 1,2,4 to reach 128GB.

[Murph_9000]

Assuming you mean the Strix Z790-A, that memory is not on the Memory QVL in a 4 DIMM config.  The "socket support" column tells you how many DIMMs are validated, and needs to be "1,2,4" for 4 DIMM configs.  The fastest 4x32 config listed is 5200 MT/s with 40-40-40-80 timings @ 1.25V for KF552C40BBAK2-64 (which is likely the same DRAM chips on your DIMMs) or KF552C40BBK2-64.

Running 4 DIMMs overclocked is difficult with DDR5.  Running 32GB DIMMs overclocked is also harder than running smaller capacity DIMMs.  Running 4x32GB is particularly difficult with overclocking.

You should always install Windows with memory overclocking disabled, to avoid getting file corruption during the install.  Once Windows is installed, you can start experimenting with memory speeds to see what will work for your particular CPU and DIMMs.  You probably won't get them stable at 5600, but 5200 may be possible.

[DannyETH]

The motherboard is Asus Prime Z790A Wifi.

@Murph_9000 

[Murph_9000]

You need to select your CPU type at the top of the PRIME Z790-A Memory QVL.  If I select 13th gen K/KF series, I see roughly the same listings that I saw for the Strix Z790-A (there might be some differences between the listed modules for the different boards, so it's important to get the correct list).  As above, the fastest 32GB DIMMs validated for a 4 DIMM config are 5200 MT/s 40-40-40-80 @ 1.25V, the same two Kingston parts I mentioned above.  Your KF556 DIMMs are likely the same as the KF552 DIMMs, just with higher binned DRAM chips and a different XMP overclocking profile loaded; the underlying chips will come from the same 4800 MT/s production lines.  There's a fair chance they might work at 5200.

The board does support 128GB and 192GB configurations, but not at all overclocked speeds.  It also supports overclocking to 5600 MT/s and beyond, but not at all possible capacities; and the highest speeds are limited to 2 DIMM configs.

[JohnAb]

Yes, 4 DIMM options are always tricky, it has been said many times, although I'm no expert at configuring RAM myself. I was looking at the PRIME Z790-A WIFI, so at least I got that right. I also noticed that there were no 1,2,4 options listed. As I thought I was going mad, I then found a QVL list for the ROG STRIX B550-F GAMING WIFI II which does have a few 1,2,4 options listed, so at least I wasn't imagining that the format is used. Can you just use 2 sticks, is that an option or do you really need 128GB?  

[B1ack0p5]

Nearly the same to me.  ASUS ROG STRIX Z790-F GAMING WIFI , a 13900K and 4 memory module (KF556C40BBK2-64)

If I use only sockets A1 and A2 the system is working (no overclocking, everything on auto) but if I but a module on channel B it will not boot. It stucks with the yellow LED on. If I put a module on A2 and B2 the system seems to reboot after some time because the red (CPU) LED flash up shortly.

[DannyETH]

Thanks everyone for taking the time to reply, I was close to going crazy today with this. I finally sorted it out.
IT works with Tweaker in Auto mode (NO overclocking), I managed to install Windows this way, installed a lot of apps, encryption and lots of other software. I also ran two memtests and everything is working smoothly, absolutely NO crashes.

So basically it looks like with 128GB DDR5 no overclocking is possible, at least for now, until Asus makes some new Bios updates, which will hopefully help.

Once I finish setting up everything, I will try to raise the clock to 5200MHz and see what happens, I will post results.

Again, many thanks to all of you, learned a lot in the process!

[kutay-akyurek]

Same problem here with TUF Z790-P Wifi D4.

A1-A2 slots stopped working after i install a new GPU. My ram modules are not on the list because of Corsair's nonsense version thing. Mine is 3.31 and mobo supports 5.39. I ordered them online so i couldn't know what version were those. Even though, before the new gpu, they worked fine together with XMP enabled on supported max speed.

I got two Corsair Vengeance LPX 3600 Mhz 2 x 16Gb kits (CMK32GX4M2D3600C18 ver. 3.31)