RAM not hitting XMP speeds

[Idkwhat2putheresowhatever]

Hey guys, I got an additional 2x8GB of Corsair Vegeance RGB Pro to bump up my ram to 32GB today. All the sticks were rated at 3600MHz, same timings, exact same model code. Even the model code was the same and so was the version number. However, I chucked the ram in and after enabling XMP, my motherboard stated that the overclock failed. I tried removing my existing sticks of RAM and putting the new ones in slots 2 and 4 as recommended by the motherboard and it hit 3600MHz just fine. However, whenever I used the 1st and 3rd RAM slot, it just refused to hit 3600MHz, even if the 2nd and 4th slots are empty. I tried bumping up the IO and SA voltage up to 1.2v and a little bit above that and that did not make any difference whatsoever. Im currently running the sticks at 3333MHz with a BCLK frequency of 102.5 (the earlier XMP tests were done before I bumped up the BCLK frequency. I only bumped it up after the PC booted up with RAM at 3333MHz)

 

My PC specs

Intel Core i7-8700

MSI Z370 Gaming M5

4x8GB Corsair Vengeance RGB Pro DDR4-3600

Zotac GeForce RTX 2060 Super

250GB Samsung 860 Evo, 400GB Intel S3610, 2TB Toshiba P300

Cooler Master V850 Gold PSU

[Haro]

Try mix and matching sticks from the old and the new kit  and try (i.e one old stick and one new stick). 

As for all 4 sticks, set the dram voltage to 1.35 and the vccio/sa to 1.1-.2 and try a lower frequency like 3200/3000, check if that's stable, and then go for 3600. 

[Idkwhat2putheresowhatever]

Just now, TofuHaroto said:

Try mix and matching sticks from the old and the new kit  and try (i.e one old stick and one new stick). 

As for all 4 sticks, set the dram voltage to 1.35 and the vccio/sa to 1.1-.2 and try a lower frequency like 3200/3000, check if that's stable, and then go for 3600. 

I tried that already. It doesnt seem to be issue with the RAM but the memory controller. All the sticks hit 3600MHz as long as it is in the 2nd and 4th slot

[Idkwhat2putheresowhatever]

Its currently sitting at 3417MHz

[Haro]

10 hours ago, Idkwhat2putheresowhatever said:

. All the sticks hit 3600MHz as long as it is in the 2nd and 4th slot

then as i said..

10 hours ago, TofuHaroto said:

As for all 4 sticks, set the dram voltage to 1.35 and the vccio/sa to 1.1-.2 and try a lower frequency like 3200/3000, check if that's stable, and then go for 3600. 

^.

10 hours ago, Idkwhat2putheresowhatever said:

Its currently sitting at 3417MHz.

I'm going to assume with all 4 sticks, then again as i said, bump the vccio and sa voltage and check.

Edited September 14, 2020 by TofuHaroto

[Moonzy]

7 minutes ago, Idkwhat2putheresowhatever said:

I used the 1st and 3rd RAM slot, it just refused to hit 3600MHz

probably bad board design then, if it's unstable at 3600 at slot 1 and 3

 

not a bad dimm since all run 3600 just fine, and CPU weak IMC wont cause slot 1 and 3 to be unstable afaik

[Idkwhat2putheresowhatever]

Just now, TofuHaroto said:

then as i said..

^.

So right now both CPU IO and CPU SA is at 1.2v. 3000 and 3200 is both stable. Bumping the IO and SA voltage does not change anything

[Haro]

10 hours ago, Idkwhat2putheresowhatever said:

Bumping the IO and SA voltage does not change anything

then it could be just the imc not handling 3600 on all 4 dimms since that is more pressure on the imc. 

you could try updating the bios and check but the difference in performance between 3400 and 3600 wont be noticeable. 

[Idkwhat2putheresowhatever]

Just now, Moonzy said:

probably bad board design then, if it's unstable at 3600 at slot 1 and 3

 

not a bad dimm since all run 3600 just fine, and CPU weak IMC wont cause slot 1 and 3 to be unstable afaik

Dang that sucks. IIRC the Z370 Gaming M5 is a somewhat higher mid range board which was why I went for it. If its the issue with the memory controller on the CPU I will be swapping to a used 9900k when one thats reasonably cheap is available in my area

[Idkwhat2putheresowhatever]

Just now, TofuHaroto said:

then it could be just the imc not handling 3600 on all 4 dimms since that is more pressure on the imc. 

you could try updating the bios and check but the difference in performance between 3400 and 3600 wont be noticeable. 

Ill update my BIOS to version 7B58v1A and let you know

[Idkwhat2putheresowhatever]

11 minutes ago, TofuHaroto said:

then it could be just the imc not handling 3600 on all 4 dimms since that is more pressure on the imc. 

you could try updating the bios and check but the difference in performance between 3400 and 3600 wont be noticeable. 

Nope didnt work. Guess Ill keep it at 3417MHz

 

 

[Haro]

10 hours ago, Idkwhat2putheresowhatever said:

Guess Ill keep it at 3417MHz

yea could be the imc not being able to run them all at 3600, either way the difference between 3400 and 3600 as i said isn't noticeable. 

[Idkwhat2putheresowhatever]

Just now, TofuHaroto said:

yea could be the imc not being able to run them all at 3600, either way the difference between 3400 and 3600 as i said isn't noticeable. 

The IMC is on the CPU correct? I'm getting an i9 in a few months so will that help?

[Haro]

10 hours ago, Idkwhat2putheresowhatever said:

I'm getting an i9 in a few months so will that help?

Generally the imc's on intel cpu's are pretty robust and should easily handle 3600, the i9 could come with a better imc.

10 hours ago, Idkwhat2putheresowhatever said:

The IMC is on the CPU correct?

Yes, the integrated memory controller. 

[Idkwhat2putheresowhatever]

Just now, TofuHaroto said:

Generally the imc's on intel cpu's are pretty robust and should easily handle 3600, the i9 could come with a better imc.

Yes, the integrated memory controller. 

Ah well then guess I'll just use it this way for now. Intel probably didnt expect many to run high frequency RAM on a locked CPU. 

[Haro]

10 hours ago, Idkwhat2putheresowhatever said:

Intel probably didnt expect many to run high frequency RAM on a locked CPU. 

Not really, i mean locked or not locked, the imc should still be decent but yea the difference between 3400 and 3600 is not noticeable  so you're not missing out on a lot really.

[Moonzy]

34 minutes ago, Idkwhat2putheresowhatever said:

whenever I used the 1st and 3rd RAM slot, it just refused to hit 3600MHz, even if the 2nd and 4th slots are empty.

 

26 minutes ago, TofuHaroto said:

then it could be just the imc not handling 3600 on all 4 dimms

hmm, but it doesnt work on 2 DIMMs at slot 1 and 3, does IMC care which slot it's in? i thought that's related to RAM topology?

[Haro]

10 hours ago, Moonzy said:

i thought that's related to RAM topology?

It is, im talking about running 4 dimms running at 3600. 

[Moonzy]

Just now, TofuHaroto said:

It is, im talking about running 4 dimms running at 3600. 

yea but if slot 1 and 3 doesnt work with 3600, changing a CPU probably wont help much i would think

 

unless a stronger IMC can help alleviate some of it?

[Haro]

10 hours ago, Moonzy said:

changing a CPU probably wont help much i would think

it is always kind of recommended to  put the ram in slot 2 and 4 since generally, a lot of boards use daisy chain. but again, OP is running 4 dimms not 2.  

[Idkwhat2putheresowhatever]

Just now, TofuHaroto said:

It is, im talking about running 4 dimms running at 3600. 

It is indeed kind of odd that XMP will only work at 3600MHz on the 2nd and 4th slots and not 1st and 3rd (by that I mean 2 sticks). If I boot the PC with ram only in the 1st and 3rd slots the board will show a screen telling me to shift it to the 2nd and 4th slots for optimum performance. I guess its maybe MSI and their motherboard design? At this point I'm not really sure if its the board or the IMC.

[Haro]

10 hours ago, Idkwhat2putheresowhatever said:

If I boot the PC with ram only in the 1st and 3rd slots the board will show a screen telling me to shift it to the 2nd and 4th slots for optimum performance. I guess its maybe MSI and their motherboard design?

No, generally a board with daisy chain topology will recommend ram to be in slot 2 and 4. 

[Moonzy]

3 minutes ago, TofuHaroto said:

it is always kind of recommended to  put the ram in slot 2 and 4 since generally, a lot of boards use daisy chain. but again, OP is running 4 dimms not 2.  

yea but if it's a board issue then getting a better CPU with stronger IMC wont solve it, no?

[Idkwhat2putheresowhatever]

Just now, TofuHaroto said:

No, generally a board with daisy chain topology will recommend ram to be in slot 2 and 4. 

Are T-topology (if thats what its called) only found on higher end boards like those with HEDT chipsets? I'm kind of a noob with these sort of things.

[Haro]

10 hours ago, Idkwhat2putheresowhatever said:

only found on higher end boards like those with HEDT chipsets? I'm kind of a noob with these sort of things.

They can be found on consumer boards and HEDT boards, they're just not common on consumer boards. 

 

10 hours ago, Moonzy said:

yea but if it's a board issue then getting a better CPU with stronger IMC wont solve it, no?

how is it a board problem though? lol. 

1 and 3 not working properly isn't really a problem, kind of happens with boards that use daisy chain topology. 4 dimms is more pressure on the imc so the imc might not get the same frequency with 4 sticks compared to 2 sticks, if OP is planning on upgrading his cpu, it could come with a stronger better imc.