Dell OptiPlex 740 Series Specs - CNET
Specs in the first link show either an NVS210 card or nForce 430. The first is not supported by either of the two nVidia drivers we currently embed and the second only lists Windows drivers under the legacy card section of the driver search app. Either way I think you have the answer.
It's not a 32-bit Linux version btw, because we dropped i386 builds ~3.5 years ago.
8.2.0 release files for RPi/RPi2 have been removed from the release/download server while cause and fix are investigated
The last 10+ releases of nvidia driver have noted some kind of "suspend fix" in documentation but it's never been the one that people have reported here so I wouldn't get hopes up.
I'd caution that nobody I'm aware of among staff uses PXE boot so there is ~zero testing done before releases, but as long as it continues to work there are no plans to remove or sabotage the feature.
What hardware and what version of OE are you updating from?
No debug log = no problem 
Hashes are worthless and are not the solution. We are working on a proper solution. Go poke in GitHub for more info.
I downloaded the driver from the link on the advert/listing but can only see references to using it on Android. It might compile on Linux but we don't have that driver in our images and honestly we have low/no desire to add more sh1t quality realtek drivers that are hard to maintain.
And I don't make hardware recommendations, sorry.
Realtek_RTL8812BU_USB_Module <= there are no known linux drivers for this chipset, so no it won't work
^ in this context "recognised" means the kernel can see there is a USB device attached, but because there is no driver in the kernel (because no driver exists for this chipset) nothing more happens.
SSH into the box and run "lsusb | paste" then share the URL generated here. Then we can tell you which unsupported chipset in the device you bought. I can see from the driver that it has a realtek chipset, but we need to see the actual USB device ID's to comment further.
I renamed the thread because it has nothing to do with the Chromebox.
Your clean install of Win10 has no SMB1 support (only SMB2/3). Your clean install of LE 8.0.2 has no SMB2/3 support (only SMB1). You need to update to LE 8.1.2 (or 8.2.0 once released) and then OS/Kodi has newly-added support for SMB2/3 connections.
You should be able to connect a USB keyboard and mount the boot partition to correct the boot command. The initramfs boot environment that you drop into when that error shows has "vi" as a text editor.
en:users:drivers:brcm80211 [Linux Wireless]
^ there is no linux driver for this chipset; throw it out (or return it if you can) and get something something else
Assuming "error in mount_flash: mount_common: could not mount LABEL-LIBREELEC" is a typo and LABEL=LIBREELEC is correct the issue is quite simple; you are trying to mount using disk (partition) labels and there is no partition with the label LIBREELEC. This is probably the boot partition, which is rather fundamental.
Add-on bumps happen because people care and take the time/effort to contribute. The more people who do this, the easier everything becomes.
I forget when we added the option but it is definitely in the 8.1.2 release, so update.
Some ISP's block NTP requests in their router firewalls. Some ISP's block NTP in their network. It's stupid, but it happens.
You can try configuring 0.br.pool.ntp.org, 1.br.pool.ntp.org, 2.br.pool.ntp.org and see if those work? - also set the LAN IP of the router and see if that works as an alternative - you'll be at the whims of the router clock but at least you'll probably get something within the same day.
