pastrychef's Asus ROG Strix Z370-G Gaming (WI-FI AC) build w/ i9-9900K + AMD 6600 XT

[skandragon]

A ram disk might work; the Homebrew installed "memtester" also wires the memory, so it cannot cause swapping, and must use actual physical RAM. If it cannot allocate enough (say, you only have 32 and you try to use 30 or so) it will fail to allocate it.

From experience, this is the best method to ensure your memory is really working while running OSX.

I'm beginning to believe either my second set of 16 GB sticks are bad, or the motherboard is bad. I'll purchase an alternate motherboard and see what happens, and try the RAM I have trouble with in the first two slots, and run a memtest on it from an Ubuntu boot USB drive.

 

[pastrychef]

If you look at the image above, the RAM disk used all the memory and there was no swapping yet. It wasn't until I started doing other stuff while the Blu-ray was playing that swapping began.

 

[skandragon]

I understand that the ram disk might be a way to test this, but my knowledge of how memory management on Unix-like systems works tells me that wired memory is guaranteed not to be swapped out, and must only reside in physical RAM, and at the specific address it is currently mapped into. The OS itself uses this for buffers it will be sending to hardware to DMA into, for instance. It ensures the memory doesn't get swapped out (which would crash a DMA operation) or whatnot, and it cannot be compressed.

It's a small little tool, easily installed with "brew install memtester", and run like "memtester 50G"

 

[pastrychef]

I understand that the ram disk might be a way to test this, but my knowledge of how memory management on Unix-like systems works tells me that wired memory is guaranteed not to be swapped out, and must only reside in physical RAM, and at the specific address it is currently mapped into. The OS itself uses this for buffers it will be sending to hardware to DMA into, for instance. It ensures the memory doesn't get swapped out (which would crash a DMA operation) or whatnot, and it cannot be compressed.

It's a small little tool, easily installed with "brew install memtester", and run like "memtester 50G"

I spent over 2 hours completing one loop of memtester. I'm not going to waste any more time. All the RAM is there.

 

[skandragon]

Great! . I wasn't trying to convince you it wasn't, I was trying to convince you to add a useful tool to your arsenal of knowledge, as you are extremely helpful.

 

[pastrychef]

If the test didn't take as long as it does, I would try a run without the manually entered RAM specs. I suspect that it may pass without them since iStat Menus sees the full 64GB with or without it.

 

[msbc42]

I'm also thinking of upgrading my current build to this board/cpu. The issues with memory is concerning me. I went to the G.Skill RAM Configurator to check if my current RAM (F4-3200C14D-32GVK) is certified - it is.

I also checked the RAM you list in #1 (F4-3400C16Q-64GTZ) and it is not listed. Could this be you're problem?

https://www.gskill.com/en/configurator?manu=29&chip=3094&model=3101

 

[pastrychef]

I'm also thinking of upgrading my current build to this board/cpu. The issues with memory is concerning me. I went to the G.Skill RAM Configurator to check if my current RAM (F4-3200C14D-32GVK) is certified - it is.

I also checked the RAM you list in #1 (F4-3400C16Q-64GTZ) and it is not listed. Could this be you're problem?

https://www.gskill.com/en/configurator?manu=29&chip=3094&model=3101

I don't think the RAM is a concern at all. I've gone through fairly exhaustive efforts to prove that it's working.

According to Asus, my RAM is on their QVL. I'm using this RAM: G.SKILL TridentZ Series 64GB (4 x 16GB) 288-Pin DDR4 SDRAM DDR4 3400 (PC4 27200) Intel Z170 Platform Desktop Memory Model F4-3400C16Q-64GTZ - Newegg.com and this is from Asus:

 

[skandragon]

It turns out I had bad memory. If I put one set of DIMMs into 0/2, the board would not POST, while the other set would POST in either 0/2 or 1/3, even though OSX would not boot if no memory was installed in 0/2. I now have 64 GB installed, and while I had to specify the sizes in config.plist to make OSX find all four sticks, things seem to be working well. "memtester" has run the first ("stuck address") test, which means every memory address was touched at least once, and there were no issues; it'd have crashed with the bad memory (or no memory but config.plist telling it there was) in slots 1/3.

Thanks again for all the advice, pastrychef!

 

[ursaperma]

Hi pastrychef. I have the same CPU and motherboard as you. I specified i7-8700K in user config and used ssdtprgen.sh to generate ssdt.aml. appleintelinfo.kext recognizes the turbo frequency (i.e. 5.0 GHz), but macOS only runs as high as 4.65 GHz. Any idea why? Thank you.