4 sticks RAM failing, but individually - pass...

[dmsq]

Hello,

I have purchased additional 2 sticks of Crucial Ballistix Elite 2x8GB (BLE8G4D26AFEA.16FAD) modules and placed them on my Gigabyte Z170X-UD3 along with other 2 exactly the same modules. Now I have 32 gb of RAM. The problem is that memtest fails.

I tried to test them in combinations of two, tested each pair for almost 50 hours, tried changing mb slots, and all those tests PASSED. But when I use all 4 sticks at once, memtest always fails.

Memtest output: http://imgur.com/nGP1nKC

I took those sticks to my friend who has Gygabyte Z170x Gaming 7 and he tried out, memtest passed with no errors with all 4 ram.

So I took my Gygabyte to RMA. When it was returned, the problem wasn't solved and memtest was still showing errors.

So I bought ASUS SABERTOOTH Z170 MARK 1. Unfortunatelly this motherboard acts exactly the same way - everything works fine with 2 sticks, but once all 4 sticks are installed memtest shows errors or shows no errors and this line:

"Note: Ram may be vulnerable to high frequency row hammer bit flips"

XMP profile is set. PSU - 650w thermaltake.

I read this thread: http://www.passmark.com/forum/memtes...er-mitigation=

I tried to reduce tREFI and tREFIX9, but it had no effect.

2 times Memtest didn't finish as the system was freezing.

I also tried to increase DRAM voltage from 1.2v to 1.3v but it had no effect either.

I tried to change PSU and CPU but it had no effect. CPU is using water cooling system, and I tried cooling RAM with a fan, but no effect there either.

When using only 2 sticks they work perfectly in any slot with no errors.

Passmark Rammon sees all RAM sticks as identical except for their serial numbers.

I tried bios 2202 and 3007 on ASUS Sabertooth.

Help mee..

[keith]

Were the errors you were getting on the ASUS SABERTOOTH Z170 MARK 1 board only in Test 13? If so, see this page on Test 13 only errors:

http://memtest86.com/troubleshooting.htm#hammer

Row hammer errors are due to inherent hardware bugs with the RAM module, so you would need to switch to different RAM that isn't vulnerable to row hammer errors.

[David (PassMark)]

The original errors in Test #6 on your Gigabyte board were likely real errors. It isn't all that unusual for 2 sticks to work and 4 sticks to fail. Typical problem is the extra power draw from 4 sticks drops the voltage slightly. You might have been able to get it to work by either increasing the voltage or decreasing the speed slightly.

Row hammer errors are not a CPU or PSU issue. (although some CPU models do have some mitigation functionality built into them).
See the link Keith posted above for more details.

[dmsq]

Hello, David!

Thanks for reply. Here is a screenshot of memtest 7.2 on my new Sabertooth z170 with all four sticks: http://imgur.com/a/FVwrc
Errors on memtest #6.

I have tried to increase voltage, but can you recommend me how much to increase it?? 1.3v?? 1.4v ??? Default X.M.P. to my memory is 1.2v

[David (PassMark)]

Try dropping the speed (i.e. don't use the XMP profiles).