Overclock.net - An Overclocking Community - View Single Post - *Official* Intel DDR4 24/7 Memory Stability Thread

View Single Post
post #10430 of (permalink) Old 11-08-2019, 10:35 AM
New to Overclock.net
moorhen2's Avatar
Join Date: Jan 2010
Location: Shanklin Isle of Wight. UK
Posts: 1,466
Rep: 49 (Unique: 36)
Quote: Originally Posted by Apothysis View Post
I'm on the XI Apex and this might be dual rank specific (running 2x16GB B-die) but has anyone had huge issues with stability (mainly RTL training) when raising VCCIO/VCCSA? I've run GSAT to verify that my current setup is stable (1 hour) at 1.1v IO and 1.15v SA but 3800 dual-rank is a pretty tall ask for the IMC and 1.1v is to low, which I've tested with Prime95 (112k in-place non-avx). The problem is that once I bring VCCIO up above 1.2v it fails training and it shows on the RTL values. Is there any other voltage (Dram VTT?) that might stabilize this? It's been super frustrating testing every combination if VCCIO/VCCSA between 1.15-1.35v and I'm getting nowhere.

What's the safest approach to tackle this otherwise? It fails training even with really loose timings once VCCIO gets high enough to stabilize the IMC For 3800 MHz dual-rank (it seems to be near 1.325v but I can't verify this due to the training fail). I've verified that the CPU itself is stable at 1.375v (52x/49x/0avx) 0.95v VCCIO (stock RAM). I'm running the cache at stock while overclocking the RAM though which seems to be the common advice.

While the board seems great at handling 2x8GB it definitely requires a lot of manual input for 2x16GB (putting some values far to low on auto training etc.).

Edit: Attached screenshots of Timing Configurator for comparison. The first picture is with 1.15v IO 1.15v SA (~1 min stable prime95 112k non-avx), the second with 1.175v IO 1.15v SA and as you can see RTL CHA D0 is off already.
You don't state what Ram kit you are using, you need to run a memory specific stability test, ie GSAT. HCI or Ramtest which I use and tests the cache as well. Also make sure you have the Mem OK Switch in the Disabled position on the mobo.

Asus Z390 Maximus XI Extreme.
Asus Z390 Maximus XI Apex.
Asus Z390 Maximus XI Hero.
Intel I9 9900K. C Stepping P0 revision.
Intel I9 9900K. (new) D Stepping R0 revision.
Custom Watercooling.
moorhen2 is offline