Question How can I fix this bizarre RAM issue ?

[JJBolas]

Hey
I have an old MSI Z270 Tomahawk board on a computer (Specs ate the end of the post) that I'm using as a server.
Today I decided to upgrade the RAM for it and got stuck on this bizarre issue.
The board has 4 DIMM slots, the old memory was 2 x 8Gb G.SKILL Ripjaws V 3200Mhz and the upgrade is 4 x 16Gb Crucial Pro 3200Mhz.
The issue I'm facing is that the PC doesn't turn on (EZ Debug light just switches from the CPU and RAM back and forth, already tried to clear CMOS, can't even go to BIOS) with the new sticks except in some weird configurations.

It's better to show what I've tried:
G -> 8Gb stick from GSkill
C -> 16Gb stick from Crucial
X -> empty slot

X G X G - Boot and RAM shows in BIOS
X C X C - No boot
C X C X - No boot
C C C C - No boot
C X X X - No boot
X C X X - No boot
X X C X - No boot
X X X C - No boot

So I thought the crucial sticks were defective but then the bizarre part happened when I tried:
X X G C - Boot and RAM shows up in BIOS
X C G C - No boot
G C G C - Boot and RAM shows up in BIOS
G C C C - Boot and RAM shows up in BIOS

Specs:
i7 7700k
MSI Z270 Tomahawk
Corsair H100i v2 Cooler
Corsair RM750x PSU


Any help is appreciated

 

[Lutfij]

Welcome to the forums, newcomer!

What BIOS version are you on for your motherboard?

 

[JJBolas]

Welcome to the forums, newcomer!

What BIOS version are you on for your motherboard?

Thanks!

I'm using the latest available at MSI website

 

[Ralston18]

This motherboard?

https://www.msi.com/Motherboard/Z270-TOMAHAWK/support#manual

Verify that I found the applicable motherboard.

From the User Manual:

"Always insert memory modules in the DIMMA2 slot first."

(Physically numbered Page 26.)

Doublecheck that both the installed RAM and RAM configuration are supported.

And that DIMMA2 is installed first.

 

[JJBolas]

Yes, that's the correct motherboard.

These DIMMs do not appear on the MSI website but if I go to Crucial website I can see that this RAM should be compatible with my Motherboard (https://eu.crucial.com/compatible-upgrade-for/msi(microstar)/z270-tomahawk)

Since I'm trying to fill the 4 DIMM slots it shouldn't matter the order I insert the sticks, right?

 

[Bob.B]

Yes, that's the correct motherboard.

These DIMMs do not appear on the MSI website but if I go to Crucial website I can see that this RAM should be compatible with my Motherboard (https://eu.crucial.com/compatible-upgrade-for/msi(microstar)/z270-tomahawk)

Since I'm trying to fill the 4 DIMM slots it shouldn't matter the order I insert the sticks, right?

It looks like you are trying to mix 2 kits of crucial ram.
That may not work very well.

 

[JJBolas]

Can't I mix two similar kits?
They're the same spec, same model and I'm putting them in the right slots (kit 1 in slots 1 and 3 and the other kit in slots 2 and 4)

 

[Bob.B]

Can't I mix two similar kits?
They're the same spec, same model and I'm putting them in the right slots (kit 1 on slots 1 and 3 and the other kit on slots 2 and 4)

Mixing is iffy.
Best to shop for a 4x16GB kit.

 

[thestryker]

What speed does the memory show up as in the BIOS when you're mixing and it boots successfully?

Also does it detect the 16GB capacity of the new DIMMs correctly?

While I don't advocate mixing kits of memory your current issues go way beyond anything of the sort.

 

[JJBolas]

Mixing is iffy.
Best to shop for a 4x16GB kit.

The 2x16GB kits are so much cheaper here...

What speed does the memory show up as in the BIOS when you're mixing and it boots successfully?

Also does it detect the 16GB capacity of the new DIMMs correctly?

While I don't advocate mixing kits of memory your current issues go way beyond anything of the sort.

It shows as 3200Mhz but running at 2133Mhz and yes it does detect as a 16Gb module

 

[thestryker]

The 2x16GB kits are so much cheaper here...


It shows as 3200Mhz but running at 2133Mhz and yes it does detect as a 16Gb module

Try setting it to 3200 and seeing if the system boots. My theory is that maybe your system isn't stable at 3200 and the new memory doesn't have a base 2133 profile. This would explain why your system would boot with the old memory as the leading module as it defaults to 2133 and forces everything else to run the same speed.

 

[JJBolas]

Try setting it to 3200 and seeing if the system boots. My theory is that maybe your system isn't stable at 3200 and the new memory doesn't have a base 2133 profile. This would explain why your system would boot with the old memory as the leading module as it defaults to 2133 and forces everything else to run the same speed.

I have just set the frequency to 3200Mhz manually and it booted (With one stick G.skill and 3 Crucial)

 

[thestryker]

Just set the Frequency to 3200Mhz manually and it booted (With one stick G.skill and 3 Crucial)

Well there goes that theory then as it's the only thing I could think of which would have that result. Check in Windows with CPU-Z on the SPD tab and see what it shows for the modules. See if there's differences between the Crucial and G.Skill modules.

The system is old enough it shouldn't have any training system, but there's definitely something different between the two.

 

[Bob.B]

The 2x16GB kits are so much cheaper here...


It shows as 3200Mhz but running at 2133Mhz and yes it does detect as a 16Gb module

Clear the cmos.
Using just 1 stick of the crucial in slot a2 all other slots empty does it boot?

Repeat the test with each stick of crucial.

 

[JJBolas]

Well there goes that theory then as it's the only thing I could think of which would have that result. Check in Windows with CPU-Z on the SPD tab and see what it shows for the modules. See if there's differences between the Crucial and G.Skill modules.

The system is old enough it shouldn't have any training system, but there's definitely something different between the two.

I don't have windows installed on this machine but I will try to see it

Clear the cmos.
Using just 1 stick of the crucial in slot a2 all other slots empty does it boot?

Repeat the test with each stick of crucial.

Already cleared CMOS and as I said in the post it does not boot with a singe stick of crucial:

C X X X - No boot
X C X X - No boot
X X C X - No boot
X X X C - No boot

 

[thestryker]

I don't have windows installed on this machine but I will try to see it

Ah yeah my brain just automatically goes to Windows every time. The BIOS will display some information and looking through the manual it looks like there's an option in the OC menu called "Memory-Z" (manual also says you can press F5 to access) and in there it should have the SPD tables. The linux command you'd be looking for is decode dimms and while I've never used it myself should have all of the relevant information. This doesn't pull current information though as far as I'm aware just the tables themselves.

 

[Bob.B]

I don't have windows installed on this machine but I will try to see it


Already cleared CMOS and as I said in the post it does not boot with a singe stick of crucial:

C X X X - No boot
X C X X - No boot
X X C X - No boot
X X X C - No boot

That's not quite what I asked.

 

[JJBolas]

That's not quite what I asked.

Not sure what you asked then, I tried a single crucial stick in each slot with the other slots empty and none booted up

 

[JJBolas]

Well thank you all, I ended up returning the RAM and buying a different kit (2x Corsair Vengeance LPX 3600Mhz 2 x 16Gb) and it's working fine

 

[thestryker]

Well thank you all, I ended up returning the RAM and buying a different kit (2x Corsair Vengeance LPX 3600Mhz 2 x 16Gb) and it's working fine

Most likely was something with the timings on the new kit the system didn't like then. XMP kits always default to 2133 and have a fairly wide array of timings available which 3200 kits don't necessarily.