Why does memory get cranky during colder temperatures?

[13oots2]

Over the years of overclocking memory with various motherboards and CPU's have had a couple play up when it gets colder. Fire up the PC when it has been sitting in a cold room for a while, and it won't post BIOS information nor boot, hard power off, and it will load default settings and go into BIOS. A quick save of the overclocked settings as nothing has changed, and the computer will post normally and continue booting into Windows without any issues. Memory and processor are fully stable at the overclocked settings and pass extended tests without errors, PSU is high quality and beefy enough for the components. Why does memory sometimes have cold boot issues, and is there a solution? Depending on how cold it gets, I may have to reduce my current memory speeds from 4000mHz to 3800mHz or even 3600mHz, something I prefer not to do. At the end of the day, it is an irritation rather than my world falling apart, and only takes a minute or two to go through the extra steps for full memory speed.

 

[13oots2]

Finally got to the bottom of my cold boot problem yesterday, had a crash and when I rebooted was missing 32gb out of 64gb on my Asus Strix X-299 E Gaming II, and the memory wouldn't budge from 2400mHz. Had a bit of a strip down and gave all the slots including memory a good blast of contact cleaner, the crud that came off the gold contacts was pretty bad. Reinstalled everything and full memory and speeds restored, needed lower voltages to get 4000mHz 16,16.16,32 with my Team Group 8 Pack 3600.

Installed latest 2001 Bios and then had problems with it killing LSI RAID 8i cards, thought 1 was age, but 2 exactly the same error then death, reverted to 1801 and my remaining spare 4i card is still alive. Asus don't make it easy to report, problems without jumping through all your personal deails.