[SOLVED] ASUS Prime Z490-A support for DDR4 4000 2x32GB?

[rasmasyean]

G.SKILL Ripjaws V Series 64GB (2 x 32GB) 288-Pin DDR4 SDRAM DDR4 4000 (PC4 32000) Intel XMP 2.0 Desktop Memory Model F4-4000C18D-64GVK
https://www.newegg.com/g-skill-64gb-288-pin-ddr4-sdram/p/N82E16820374047?Item=N82E16820374047

I got the above to go with an ASUS Prime Z490-A.
I tried the XMP, but it didn't work.
I did manual and set it to 3600 since it looks like all the other "compatible RAM" maxes at 3600.

PRIME Z490-A｜Motherboards｜ASUS Global

www.asus.com

Will a future bios (I got the latest beta) be able to support it, or is this a hardware limit for this size of RAM for this board?

Thanks!

 

[Darkbreeze]

That memory kit IS validated for that motherboard, according to the G.Skill memory configurator. Which slots do you have the memory installed in?

They SHOULD be installed in the second and fourth slots over from the CPU, which are the A2 and B2 slots. If they are not in the slot closest to the edge of the motherboard and then the slot that is two slots over from that one, which are the two lighter gray slots, then move them to those slots and then try again.

If they ARE in those slots, try removing the memory and reseating it in those same slots. If that fails to work, then it's possible you have one of a couple of other problems such as a CPU cooler that is tightened unevenly and is causing the CPU to cock in the socket, or a CPU with bent a bent pin or two, or a bad memory module, or two memory modules that did not come together in one kit but were purchased as separate sticks of memory.

Additionally it may be necessary to bump up the DRAM voltage in order to run the kit at that high speed depending on how strong the internal memory controller in YOUR specific CPU is. Not every system will run the same even with the same hardware configuration. I would at some point try setting the XMP profile but THEN as an additional step, find the DRAM voltage setting and increase the DRAM (memory) voltage by .005v. Save settings and exit BIOS. See if it will post and if it will you will then probably want to run Memtest86 for four full passes to validate stability. If it does not, try increasing by another .005v and same process. You should be fine up to a total of .020v increase and if by then you don't have stability then the problem is likely not due to the DRAM voltage, but is something else entirely.

 

[rasmasyean]

I reseated it and it worked.

Now that you mentioned, I had installed the CPU cooler after the memory. Could it be that me bending the motherboard via the pressure of the clicking mount heat sink may have loosened the RAM connection ever so slightly that it doesn't conduct perfectly at high speeds? Is that what you mean? Is that a "contact resistance" effect?

 

[Darkbreeze]

It's certainly possible. It's equally possible though that often with new hardware something just doesn't "quite" make a good connection, and reseating it just slightly removes maybe that superficial layer of oxidation on the contact surface, or whatever. Might have just not been sitting exactly right. Could as you say have flexed and something lost contact somewhere. Most of the time there is no clear cut answer for why simply removing and reinstalling something "fixes" the problem. Just be happy that that was all it was would be my advice. LOL.

 

[rasmasyean]

OK, you want to hear something really weird?

I found a new BIOS (1003 - 12/23/2020) and updated it.
Then SAME problem with XMP!
Then I reseated the RAM again...and it solved the problem again!

What the heck's happening here? It definitely doesn't look like a hardware or contact issue.
Is there some persistent memory that is corrupt on BIOS update but is "reset" when you remove the RAM sticks?

 

[Darkbreeze]

Actually, that's pretty common. I always recommend starting over with fresh settings by resetting the BIOS and re-entering any custom settings all over again anytime you update to a different BIOS version or make major hardware changes.

Often the hardware tables and settings get "stuck" in these scenarios and need to be coerced into resetting themselves through actively resetting the BIOS and reconfiguring it's custom settings. Removal of hardware itself sometimes forces that to happen as well.