I say the 4266 kit I got 16gb of 4800 gskill royal but still waiting for a my 3080 ultra gamming card so hopefully run stable at 5k+

Same here got the z490 dark anything over 4400 doesnt Boot, no matter the Sa io or dimm voltage.
Setting skews or cl 18 doesnt help.
On my Asus apex and msi ace i can Boot 4600-4700 and on this board 4400 is the Limit lol.
Got newest Bios and got knowledge About memory oc but this board is completely trash.
PCIe Soundcard is not recognized also and Bios freezes all the time when ajusting settings.
Really weak for this price, im used to better quality from evga.

Nealx01
If your having bios freezes and devices not recognized then you should be opening a support ticket or returning it. Thats not normal.

I find i need significantly less sa and IO on the dark than on my apex. And I can boot speeds and timings I can't do on the apex. And I dont mean with a bunch of fiddling either. I dont have to fight the board nearly as much. The apex is pretty darn good too...but the dark is a whole nother league, I wish your experience was as good as mine. Im running the KP version, so I cant speak for the normal version. I really would be surprised if it was dramatically different tho.

Z490 dark and kingpin look the Same but are different Hardware revs.
Dark was rushed and kingpin with the errors fixed came 2-3 months later.
There is night and Day between the dark and kingpin in Terms of mem oc.
For Training 4400mhz the board needs 2-3 minutes, which is....absurd.
Nothing helps. Not Sa Not io Not vdimm or odts.
I bet if i could get the kingpin Edition here in germany i would do great with it, but the normal dark is completely limited in its mem OC capabilitys.

Just tested again.
Z490 ace boots up to 4700 dual rank, maximus XII Apex boots 4700, dark Stops at 4200 with newest Bios and i tested all Bios.
1.07 and 1.08.

Trollsies
I bought this mobo to hit 4800mhz+ but it won’t even boot at 4700 30 30 30 62. Not sure what’s up. Is mobo faulty or is something else wrong? I tried 1.7v dram, 1.55v vsa/vccio, but no dice. It’s either mobo, 10900k imc, or the bdie Gskill 4266 kit itself.

I have the regular z490 dark and im easily able to boot and bench 4800mhz. I have tested 2 cpus and both could do 4800mhz. They both required very different vsa and vccio voltages though. If voltages were just a little to high the board would not train or boot. Remember the z490 dark overvolts too, so your actually getting higher voltages then whats set in the bios. Vccio set to 1.2 in bios is actually 1.27 tested with a multimeter.

One cpu I tested took 1.45 vsa, 1.4 vccio, and 1.5 dimm to boot, train, and bench at 4800mhz. It would not train or boot 4700mhz with those exact same settings though, it required lower voltages. My other cpu took 1.3 vccio, 1.35 vsa, and 1.47 dimm to boot, train and bench the exact same ram at 4800mhz.

I suggest starting @ 4400mhz and work your way up while keeping all other timings on auto. Just work on frequency first. Try 4400mhz with 1.43vs dimm, vsa @ 1.2, vccio @ 1.15. If that doesn't work increase each .025v and try again. If that works next try 4500mhz and raise vccio and vsa by .025. Remember keep all other timings at auto for now. Sometime you even need more cpu voltage to get certain ram speed stable. What is your cpu and cache overclock by the way and with what settings?

https://www.newegg.com/g-skill-32gb-288-pin-ddr4-sdram/p/N82E16820374048?Description=g.skill+32gb+4266&cm_re=g.skill_32gb+4266-_-20-374-048-_-Product#
 
Luumi says this is the best memory to overclock on the Z490 Dark KP ever. I would like to have it in RGB, is the Trident Z memory with the same 4266 and memory timing the same memory just with RGB or are they different. He said the best thing about the rip jaws V is the doubles sided memory. Here’s the YouTube Video
 
https://youtu.be/aeZkSFx0JHg