Aurora R16, memory errors on new machine, but only when cold

Just got a new R16, turned up last Thursday, but only started to do "the main setup" this week, and... it's not been good. The very first time I plugged it in to everything, turned it on, and the power button was flickering some error codes. So did usual thing when starting to deal with this, turned it off, made a cuppa, sat down at other machine, looked up what flashing code could mean, had page up, went back to R16 to try again, and... it worked. "hmm, maybe... don't know, but ok". Ran all the windows updates, the Dell updates, all seemed to be working fine.  Powered off, next day, went to start again, and... same error.  2 orange beeps, 4 white. Checking the page "Oh, memory error/validation". Turned it off, on again, and it went in fine. Ran all the tests in windows, came back fine.  Rebooted to the bios and ran a complete test, and, nothing found. Back into windows, all is well. I turn it off for a few hours, start it up, and memory errors. If I leave it a few minutes and reboot, it's fine, no errors found. So I'm guessing some thermal creep? something off? But what do I do for support. That this is a brand new machine, and it failed to boot the very first time, I'm a bit twitchy about making it my main rig for the next 4+ years if it's failing already. Anyone had the same issue and it's just "oh, pop the ram sticks around and it'll never be a problem again".  Or is this a sign of something more serious. Oh, and one more thing, power saving. That it was a new machine, I'd not set it to "just turn off the screen but keep running", and when it goes to sleep, it won't come back.  I have to power cycle. Anyway, just opened a support ticket, it's the memory/other experiences I'm curious about if anyone else has encountered. And if this is a lemon, how long do I have to send it back for a refund?