Defective DIMM slot on m/b - how likely?

[douglasl]

I get system crashes and memtest86 errors when I have 4 DIMMs installed, even if I rotate the modules. (That is, the problem does NOT seem to be a single bad memory module.) No matter which module is in which of the 4 slots, the memtest86 errors are all in the same narrow range - 19.968 GB to 20.0923 GB of 232 GB.

If it's not a defective DIMM, how likely is a defective DIMM slot on the motherboard?

Yes, the memtest86 site asks, "Why do I get errors only when testing RAM modules together, and not when individually tested?" . But of the two suggested reasons, my 4 modules are NOT mismatched and they ARE on the ASUS approved memory list.

I want 32 GB for graphics. So I'm thinking of going from 4x8 to 2x16, since everything works fine in slots 1 & 2.

I appreciate your comments or suggestions! Thank you,

-Doug in Seattle

 

[azaran]

Yep, I've run in to it a few times. Assuming there isn't a DIMM issue, then it sounds like you have a defective motherboard. Rather than buy all new RAM, I'd RMA the motherboard and get one without an inherent hardware flaw.

 

[13thmonkey]

can you replicate the error by testing the same stick in each slot sequentially. If you can tell that it is slot 3, then this is grounds to RMA it, you have a warranty, use it.

 

[douglasl]

can you replicate the error by testing the same stick in each slot sequentially. If you can tell that it is slot 3, then this is grounds to RMA it, you have a warranty, use it.

You mean boot the system with only a single stick in slot 3 and run the memory test?

My motherboard manual has a map of where to install DIMMs if you have 1, 2, 4, and so forth. I've never known whether the world would come to an end if I disobeyed the map or not.

 

[13thmonkey]

Start off in slot 1, run tests, it will pass or fail, switch off, try slot 2, etc.

 

[SkyNetRising]

I appreciate your comments or suggestions! Thank you,

4 modules require command rate setting to 2T. You may also need to increase memory timing values.

Can you post screenshots from CPU-Z memory and spd sections?

 

[douglasl]

I'm running memtest86 some more now so I can't check the BIOS settings.

Would incorrect command rate or timing settings really affect only such a small slice of the memory address space? All the errors are consistently in that narrow range.

Another strange circumstance is that the new system ran flawlessly for over a month, then suddenly began crashing every 15 minutes.

Thanks for your input!