Can RAM slowly fail?

An0maly_76 · August 4, 2022

So, as some might be familiar with, I did a 5900X / RTX3060ti build with an Asus TUF B550-PLUS back in March. I fitted out with WD Blue SN570 1TB and a 2x16 CL16 Ballistix DDR4-3200 kit. Over a few months, I experienced several cold starts with no video, which eventually were found to be POST failure on DRAM. I tested both DIMMs individually, both passed. Either would boot the system without issue, and since the board's debug lights resembled a traffic signal gone haywire even after swapping DIMMs and GPU, the board was presumed to be the issue and is currently in the diagnosis phase of RMA. Sounds simple, right?

Anticipating a lengthy RMA process, I snagged a cheap ASRock B450M-HDV and used 3600X, using the existing SN570 and one of the existing 16GB Ballistix. Seems to run great, albeit with a constant hourglass symbol, with no excessive RAM, CPU or GPU usage in Task Manager. I thought perhaps installing the other DIMM might help this.

No boot with the other DIMM in the second slot. I double-checked for proper seating and tried again, still no boot. The plot thickens... On a hunch, I removed the existing DIMM it was booting with and replaced it with the now-suspect DIMM. Still no boot. Swapped it out for the known good one, fires right up.

What's interesting about this is that these DIMMs registered with the Asus board as a full 32GB from day one until the day the system was dismantled for RMA. I always thought RAM was either good or it wasn't. But is it possible for a DIMM to slowly get flaky until it goes completely bad? That might explain the intermittent nature of my issue with the original build, but is it also possible that a bad DIMM could have slowly damaged the board?

BiotechBen · August 4, 2022

Ram can go flakey before completely failing. I have an LPX stick that anything above 2666 it has a seizure and causes all kinds of weird behaviors, and the other dimm is fine to 2933 where my mem controller and mobo start being the issue.

An0maly_76 · August 4, 2022

Just now, BiotechBen said:

Ram can go flakey before completely failing. I have an LPX stick that anything above 2666 it has a seizure and causes all kinds of weird behaviors, and the other dimm is fine to 2933 where my mem controller and mobo start being the issue.

So my issue could have been both, then. I don't feel quite so stupid now.

An0maly_76 · August 8, 2022

So, today the machine the one good operating DIMM is in started experiencing inexplicable glitches with audio cutting out, sometimes audio and video both, but it seems only while gaming. Playing back an MP4 doesn't seem to do it. Can a failing DIMM do this sort of thing? I figured it would be a full-on crash, not audio and video glitches.

Also found a viable theory about what my initial problem was. It seems that Crucial made this kit in both single rank and dual rank, but mainly dual rank, apparently. While some say dual rank is better for gaming, it would seem that my Asus board is quite picky about dual rank, as only a handful of the kits on the QVL are dual-rank. The Patriot VIper 4 Blackout I'm about to order for the redux is single rank, one other Patriot kit on the QVL is dual rank also, but I think it is a different set of timings and different voltage altogether. So is there a correlation of some sort between certain timings working better with dual rank over single rank, at least at certain speeds, or maybe with XMP / DOCP altogether?