AMD 7840U Not Posting

My new 7840U board arrived today, but it would not display anything on the screen (or external displays) at all. No BIOS, no nothing. Blink code is wggggggggggggrbgbggggg.

The first thing I suspected was the Crucial 2x16GB 5200MHz RAM kit I installed, which isn’t on the compatibility list. I figured that it not being on the list just meant that it hadn’t been tested, was I wrong?

Looks like the blink code might might be “SMM_IDENTIFY_FLASH_DEVICE”, though I’m not sure what steps I should take to fix that. Someone in the Discord server said that it might be missing the BIOS, so I contacted support.

Several others on here had odd, failure to post issues with the Crucial 5200MHz RAM.

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5200 MHz RAM is incompatible, unfortunately.

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Ah! Just put mine together and having similar problems. But for me the screen is completely blank. Tried 2 known good chargers and left it charging for a couple of hours. Charging light went from Orange to White after an hour or so, but nothing happens when pressing power button. I have one 32GB Crucial DDR5 - 4800 (was in my draw!)
Do I have the same problem as the OP?
Thanks in advance.

Just in case anyone is following this thread - I changed RAM to 1 x 32GB Crucial DDR5 5600Mhz and the laptop works fine.

Thread here: Suggestions for available RAM on 7640U - #3 by HoppySpadge

+1 on Crucial DDR5 5200Mhz (2x32) flat out not posting. Posted just fine when I put in Kingston 5600Mhz

Got 5600 MT/s memory, same brand. Works great.
I see that the compatibility list only shows 5600, but it would have been nice if they let us know what will not work in addition to what will.