So this past weekend I picked up a Z690 Classified and grabbed some Kingston KF560C40BBK2-32 memory to go with it, they're rated for 6000MHz and claim to be "XMP certified." When I enable any XMP profile, the system becomes unbootable and I need to hit the CMOS clear to get back on track. The BIOS version is v1.10 and it doesn't seem to provide any sort of sane error code on the board. Some guidance or suggestions would be appreciated.

I'm sure some of the other z690 owners will weigh in when they get a chance with some tips, but I will note a couple things I can note from what I've seen from others here:
 

repo1979
I would check the qvl for that board to make sure they work well with it

 
1. This^ is not a thing that exists. EVGA hasn't published a qvl for memory for their last several motherboard launches (z590, x570, z690). Sometimes you can go to the memory vendor and they'll have EVGA's motherboard on their list...which is helpful.
 
2. XMP is never a guaranteed thing to work, especially the last couple years. It used to be a pretty sure thing if you were within the specs of the motherboard, but that seems to have changed. At least with the 11th gen, and to some extent 12th gen, there's a bit of a lottery you have to win between CPU IMC, motherboard quality, and memory compatibility. It says on Kingston's PDF Spec Sheet: "Some motherboards or system configurations may not operate at the published FURY memory speeds and timing settings". That's a generic cover your behind statement from them, but it is just the case lately. Lots of folks have been posting in these threads that they've had better luck with EVGA Classy and Dark than other brands they've tried, but some kits still just don't go to the XMP speeds in their setup. You can search around or hope others will post here with what's been working for them.

Gadfly, thanks. That's the kind of tip/suggestion I was hoping people who have z690's would pop in and give lol.

Thanks for the advice, but that doesn't seem to have worked. XMP profile 1 set the VDD to 1.35v, so I matched VDDQ to 1.35v as well along with the rest of your suggestions, no dice. It appears to be in the same initialization loop spitting out error codes 4C, 31, 28, 7F and rapidly flashing several others. (Most of them appear to be undefined/reserved generic errors and undefined memory errors according to the manual) Seems it's just not wanting to play ball, which is unfortunate. Guess I'll just hope for a BIOS update in the future which might improve stability. The provided default of 4000MHz is good enough in the meantime, even if it is a bit short of the promised 6000.

Sounds like your cpu imc doesn’t want to play ball. Not surprising when the imc is only rated at 4800 MHz.

Interesting. Looks like the op is going to stick it out at 4000 MHz. Wish he would try some different dimms, or another board for confirmation.

TallonRain
Yeah, in my experience over the years the IMC tends to rank rather low in frequency limitations.

That's odd. My experience has been exactly the opposite.

TallonRain
It may be worth noting that I am indeed running 4 DIMMs in this case - two pairs of the aforementioned RAM for a total of 64GB.

Yeah, in my experience over the years the IMC tends to rank rather low in frequency limitations. I’ve regularly run RAM over the rated speeds without issues. In this case I am indeed using a i9-12900K. Supposedly it should manage 4800MHz, but in this case that value is also not working. Nor is XMP profile 3, which sets the speed to 4000MHz even though that’s the default speed it has fallen back to. It merely changes the timings and voltages.

It’s very likely the root of the issue is the motherboard. Swapping it out right now would be a hell of an endeavor with no clear gains, so I’m hesitant to try that.

Probably should have researched more. Getting 4 dimms of ddr5 to do anything over 4800 is very very unlikely. You can take a look at other motherboards qvl's as an example.

Memory manufacturers aren't putting out many 4 dimms kits (and definitely not anything over ~4800 max) for a reason.

I would suggest buying a 2x32 kit if the 64gb is needed. Newegg has them up to 5600 and would be cheaper and perform wayyyy better than your current setup.

I learned this the hard way too....4 DIMMs (Crucial DDR5 modules) to give me 128GB of RAM...

It would post but be unstable running at 4800 (XMP Profile 3) and RAM testing would fail with random errors. Came in here complaining, expecting it to work, and not knowing that Intel shifts spec as you add more sticks.

Tried XMP Profile 2 (4400, I think; going off memory...lolpun) and it runs perfectly fine. Lower latency/timings anyway so why not. I doubt I'd recognize the difference.

when someone has a board that is up and running with certain settings..post a video of each bios page and settings for others to use as a basic guideline. i know not all boards/cpus act the same but a starting point is a very useful tool. also which bios it has been updated to. i usually run asus boards but im considering another direction since i cant find one i like that doesnt have issues...one of the issues they have is the xmp not working just like this guy is having.