Question do all ram kits support xmp?

[xXiNTeRuPTioNZz]

hi, i have an older system and have recently decided to put an extra ram kit (different modules) in my system but have noticed that it doesnt have an xmp profile, if i take out my old ram and go to bios there is no xmp option but if i put both kits in there is xmp option. if i enable xmp and try to run ram at 1866mhz, which both kits are rated to run at, it fails to boot however if i set it to manual and put them at 1800mhz it works fine.

so my questions are, is there a way to get both kits to run at 1866mhz and if there is, is it actually worth doing.
my specs-
asus maximus hero 6 motherboard (z87)
i7-4790k
8gb corsair vengence pro series (2x4gb)
16gb yongxinsheng (2x8gb) (this is the one im seeing no xmp option)
asus strix rx580 oc 8gb
corsair cx 750 psu

thanks

 

[rgd1101]

new ram kit might be native 1866 without needing xmp profile
or it might just be the cheap kit that don't have xmp profile

 

[Koekieezz]

if the 2x8Kit 1866 then you could match the xmp voltage for dram, but let the timings the same as the 2x8gb ones. IMO mixing different capacities in ram and trying to run it at high rated speed, need some tuning in the timings such as tRRD, tWTR, tFAW, etc. But in my experience, i would like to leave it at default jedec timings, cause it is better to do 4x8 if you do want to run it at good timings and high freq. Not all ram chip and pcb were made the same, so it would be tricky, and the worst part is that the smd caps could fall off due to different timings (i had this many times during ddr3 days, no voltage added or decreased, just simple timing adjustments on 4 and 8gb ram, with the 4gb ram failing due to diff pcb and i adjusted the timings).

 

[geofelt]

You are starting at a disadvantage with two separate kits.
Ram is sold in kits for a reason.
A motherboard must manage all the ram using the same specs of voltage, cas and speed.
The internal workings are designed for the capacity of the kit.
Ram from the same vendor and part number can be made up of differing manufacturing components over time.
Some motherboards, can be very sensitive to this.
This is more difficult when more sticks are involved.
Ram must be matched for proper operation.

You can sometimes compensate for errors by increasing the ram voltage in the motherboard bios if you have a motherboard that permits such settings. Z87 should be ok.
The xmp settings are a short hand way to set the specs to get advertised speeds out of that module.
It is unlikely that both of your kits behave the same settings embedded.

You might be able to increase the speed from 1800 to 1866 by increasing the ram voltage a bit higher than what you get at 1800.
If it boots,
Run memtest86+
It boots from a usb stick and does not use windows.
You can download it here:

Memtest86+ | The Open-Source Memory Testing Tool

Memtest86+ is an advanced, free, open-source, stand-alone memory tester for 32- and 64-bit computers (UEFI & BIOS supported)

memtest.org

If you can run a full pass with NO errors, your ram should be ok.

Running several more passes will sometimes uncover an issue, but it takes more time.
Probably not worth it unless you really suspect a ram issue.

 

[ohio_buckeye]

This is correct. On my current build my kit doesn’t seem to have that ability. But I need to build a cheap system for my wife later on the replace her existing old Dell windows 10 pc. So when I do that I think I’ll pass my ram to her since she’s just doing office work etc on it.