RAM not overclocking

nickf23 · 25 Dec 2018 at 21:06

Hi guys , hope Xmas is being kind to you . I have 2 packs of Team Group Xtreem " Edition" 16GB (2x8GB) DDR4 PC4-32000C18 4000MHz Dual Channel Kit . When I first boot for the day , my PC will not post past memory check . I have to go into BIOS and clock it down to 3866 MHz . it will boot fine from there . if I run PC for about 30 mins and retry @4000MHz , boots fine . I can then shutdown and boot up as many times as I like , even leaving it shutdown for several hours , and it will quite happily boot with RAM @ 4000MHz . I am I missing something ?
Regards
Nick

Apone70 · 25 Dec 2018 at 23:42

What motherboard and cpu?

nickf23 · 25 Dec 2018 at 23:49

Maximus XI Formula & 9900k both on a custom water loop

Apone70 · 26 Dec 2018 at 01:05

With that board 4000mhz should be easy. When you say 2 packs do you mean 4 x 8gb in total?

nickf23 · 26 Dec 2018 at 11:48

yes . As I say after about 20 - 30 mins system will happily overclock the RAM to 4000MHz . Did it again this morning , downclocked to 3900MHz all ok and booted on same voltage ( 1.4v ) and same timings ( as set up by overclockers )

Apone70 · 26 Dec 2018 at 12:22

Try C19 instead of C18 or just 2 sticks at XMP. 4 sticks could be your problem

nickf23 · 26 Dec 2018 at 15:11

Have set to 19 , system is running at 4000MHz ok at the moment . I will see how it does when I boot tomorrow . I appreciate the advice . Any Idea why it lets me increase to higher rate once PC has been running for a while , then not the next day ?

Apone70 · 26 Dec 2018 at 15:14

8pac is really good at replying when it comes to his memory, maybe see how you get on at c19 then ask in the ask 8pac section.

nickf23 · 26 Dec 2018 at 15:20

ok , thanks for the tip .

Smffy · 30 Dec 2018 at 08:10

nickf23 said:
ok , thanks for the tip .

Set the overclocking mode to XMP not manual timings? (Sorry if you did hard to know).

Potentially just the use of 4 dimms needs slightly lower speed but above might solve it.

orbitalwalsh · 30 Dec 2018 at 09:56

Two factors, CPU IMC... Not every CPU is the same . Also Asus specialist In 2 stick testing, MSI and Gigabyte focus on 4 sticks, latter slightly behind the rest in speed bar £400+ board

4000hz on for Dimms is a lot on the IMC and board .

I pump 1.7v through those Ram sticks on daily basis , sometimes helps if it's ram issue

Try two sticks with some good long testing , swap again for other two sticks then try four. Guessing it's just CPU