General getting started

[James Good]

Lots of complaints, but a real lack of details
I have a guess, but 1st, some information for you
Except for cell phone, arm is a newish computing technology
Sure, there have been SBC, usually not that powerful to do complex things
And rPi, has a vendor supplied binary blob, video + bios
You know, I hope, that all x86 have a bios, that does low level management of hardware?
If you update with WRONG bios, usually(nearly always) computer ends up in trash
idbloader + uboot + ATF is equivelant to bios, humor me, when I say bios I mean uboot+
I have found, by experiment (and bad luck) that if you try to boot with wrong bios,
the pbp appears dead, only charging led.  Also, if there is NO bios also dead
So, I bet that there was something on the 128, but wrong
Recovery is,,1) remove bad bios (recently found this essential)
2) if bad bios on emmc, disable  3) put good, bootable SD card in
4) extra long press (pwr button,20+s)  5) normal start, 1s press
6) try a second time, hold longer 7) try a different good card
That it remembers is, I think, because there is a battery
OR, perhaps you have emmc disable switch wrong?
When they say enable, they mean shorted = emmc disabled ,, this is a bad description
To troubleshoot, always simplify as much as you can, then add until it breaks
So, no emmc, only good SD,  maybe extra long press
Questions:
Do you have emmc carrier/dongle?
Did you write something on 128?  What?
What was on the 64?
What did you expect for $200, you certainly got fairly nice hardware for that

Thank you for this reply.  Yes, for $200.00 there are several options, some of which are better (some much better) than others.  Still, when I ordered the PBP I was wanting to learn the Linux programming language.  I had recently gone through a bad experience with a Windows 10 update/upgrade that has totally burned me out on anything 'Windows' in the future.
No, I do not have the carrier/dongle.  I tried to order one but PayPal did not want to accept the credit card I use.  Yet another minor problem or distraction.
What actions I took before posting the message you refer to were:  I powered the PBP off and removed, or opened, the back of the case.  Then I removed the 128 GB eMMC module and replaced it with the original 64 GB eMMC module.  I pressed the 'Reset' button and made sure all other connections and controls were in the original position/condition.  Then I closed the case and secured everything.  On power up, (short or normal hold of power button, about 5 seconds) there was no indication of any sort.  No power LED showing, no log-in page.  Nothing.  I had already tried all of the suggestions that others on this forum had suggested without any success.  Yesterday I downloaded a new copy of the Manjaro ISO and saved it to the desktop of the main computer (which runs Ubuntu 18.04.5 LTS).  I will reuse a micro USB card by first clearing (wiping or erasing and reformatting) the card then burn the ISO file to the card.  After that, I will use that micro USB card and attempt to boot the PBP.  Honestly, I do not expect the results to be much different than the last attempt.
Thank you again.
James Good