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I purchased a phone that was suppose to be setup for verizon, i got it home and found out it had been rooted and set up for criket.
after many hours of reading and searching i have the phone flashed back to factory settings, but, when i dial *228 to program for verizon it still calls criket.
I was told i need to flash the antenna ?? or something like that...
can someone help me with this.. thanks
have you flashed the stock sbf?
follow these instructions
i cant post links, wtf
instead of flashing the 2.1sbf file listed there you can use the 2.2 file from this site
i cant post links, wtf
the radios are also listed there, i've been told you need to flash the radios in order, meaning you can't just start at the last one, you need to flash each one seperately. BUT i have no idea how to flash a radio on a stock phone, so if i were you i'd attempt the spf flash with rsd lite, then root the phone and install sprecovery, then install the radios one at a time.
I had the same issue and went to Verizon today and had them flash the stock Froyo using RSD Verizon software. Make sure you enable USB debugging first.
Sent from my Droid using XDA App
OMG... i was told i had to have the phone rooted.. i just got done rooting it again
so... it needs to be un-rooted for me to take it to verizon to get it working on there network ?
No need to unroot; just bring the phone to Verizon and they can restore it back to the original 2.2.
Hello everyone,
Not quite sure where else to put this, but I can't reply in the android dev thread since I am a new member.
I flashed (using SafeStrap 3.05) the newest stable Avatar rom for D3 (using CM 10.1 and android 4.2.2 I think) and it booted ok, mostly everything seemed to work fine (except for camera but that seems to be expected) however I have absolutely no cell service. Not even just data, but the basic cell service for texts and calls isn't on. I tried doing the Verizon activation call, but it would tell me to turn airplane mode off, (which I did, but it either seemed to turn itself back on or not matter if it was on or off anyways).
Has anyone else had this problem and has a work around for it?
Thank you
apefist said:
Hello everyone,
Not quite sure where else to put this, but I can't reply in the android dev thread since I am a new member.
I flashed (using SafeStrap 3.05) the newest stable Avatar rom for D3 (using CM 10.1 and android 4.2.2 I think) and it booted ok, mostly everything seemed to work fine (except for camera but that seems to be expected) however I have absolutely no cell service. Not even just data, but the basic cell service for texts and calls isn't on. I tried doing the Verizon activation call, but it would tell me to turn airplane mode off, (which I did, but it either seemed to turn itself back on or not matter if it was on or off anyways).
Has anyone else had this problem and has a work around for it?
Thank you
Click to expand...
Click to collapse
Do you have a sim card in the phone? This was an issue with some Jellybean/ICS roms. It happens to me as well. For some reason when placing a sim card in the phone(it doesn't need to be active) it allows your phone to get reception.
pandam00nium said:
Do you have a sim card in the phone? This was an issue with some Jellybean/ICS roms. It happens to me as well. For some reason when placing a sim card in the phone(it doesn't need to be active) it allows your phone to get reception.
Click to expand...
Click to collapse
Hey,
So this actually worked, thanks for the heads up!
step by step
apefist said:
Hello everyone,
Not quite sure where else to put this, but I can't reply in the android dev thread since I am a new member.
I flashed (using SafeStrap 3.05) the newest stable Avatar rom for D3 (using CM 10.1 and android 4.2.2 I think) and it booted ok, mostly everything seemed to work fine (except for camera but that seems to be expected) however I have absolutely no cell service. Not even just data, but the basic cell service for texts and calls isn't on. I tried doing the Verizon activation call, but it would tell me to turn airplane mode off, (which I did, but it either seemed to turn itself back on or not matter if it was on or off anyways).
Has anyone else had this problem and has a work around for it?
Thank you
Click to expand...
Click to collapse
Hey, Glad u got your issue resolved..
i am getting my first Android phone (Droid 3 XT862 Gingerbread 2.3 ) and i want to install a custom rom the same way u have..... i was wondering if you or anyone else on the forum could give me step by step guide on how to go about installing the custom rom with the ability to revert back to my original stock OS wen i need to......
i had posted a thread here http://forum.xda-developers.com/showthread.php?t=2378162 and i got some good advise so far:
you or anyone here could reply with the instructions i need or at least send me a link to a tutorial .... as i said this is my first Android so i really dont want to make any mistakes while doing this..
THANX MUCH !!!!!!!
Tha slayer said:
Hey, Glad u got your issue resolved..
i am getting my first Android phone (Droid 3 XT862 Gingerbread 2.3 ) and i want to install a custom rom the same way u have..... i was wondering if you or anyone else on the forum could give me step by step guide on how to go about installing the custom rom with the ability to revert back to my original stock OS wen i need to......
i had posted a thread here http://forum.xda-developers.com/showthread.php?t=2378162 and i got some good advise so far:
you or anyone here could reply with the instructions i need or at least send me a link to a tutorial .... as i said this is my first Android so i really dont want to make any mistakes while doing this..
THANX MUCH !!!!!!!
Click to expand...
Click to collapse
Hey, so this was my process.
First, I made sure that the stock software on the phone was up to date. I did this since that way if you have to go back to stock, you are on the latest version, and you can confirm that you are using the correct rooting application. The root tool I link to below will work on 5.7.906 which I believe is the latest.
Second, root your phone. You will need to go HERE to download the tool. Follow the instructions on the page, and it should go fine. The phone will reboot several times during the process, this is normal. Once the program says it is done, you can go check for the Superuser application in your app drawer (it might be SuperSU or something similar, I can't quite remember).
After you have root access on your phone download the safestrap application for Droid 3 HERE. Make sure you get the one that is specifically for Droid 3. Transfer that file (should be called Droid3Safestrap-3.05.apk) onto your phone.
There are a few ways to transfer files onto your phone. You will also need to do this later to transfer the .zip of whatever ROM you decide on). If you have a micro-sd card that you can put into your computer, that works. Or, you can have the phone on and plug it into the computer and transfer it that way. I believe you can transfer to either the micro SD or the internal memory. I prefer micro SD since you might want to wipe the internal memory to fix things or switch ROMs.
After the .apk is transferred find where you put it using a file manager (I personally use Root Explorer but I think Astro or stock will work), and install it. Go to the new app and run it and it should request root access, which you grant, and it should flash the recovery.
Once you have the recovery installed you can install whatever custom ROM you want, pretty easily. Safestrap is great because even if you screw up the ROM somehow, you can always just boot back into Stock.
Here is where you'll have to chose what custom ROM you want. Now as far as I know, the Droid 3 is fairly limited in its ROM selection. It does have a Cyanogen Mod 10 version, but it is not a stable version and in my experience, doesn't run super great. If you want to try Cyanogen Mod 10, I actually suggest you get the Avatar Rom variant HERE, but keep in mind that apparently you do need a SIM card inserted for the cell signal to work at all. Overall it did seem to run fairly choppy but they are still releasing newer nightly versions (July 20th was the last) so it might have gotten better. One thing to know about these ones is that the camera does not work at all, so if that matters to you just skip these.
Now those two (CM 10 and avatar) are ROMS that will bring the droid 3 up to Android 4.2 Jellybean. If you don't care about getting up to the latest version (Jellybean actually isn't the latest anymore but still pretty darn close), then there are a few other Gingerbread ROMS out there that work a bit better.
HERE is a list of a few other droid 3 ROMs, my favorite Gingerbread one that worked overall really well and stable was Steel Droid. Otherwise, you can just look around and see what's available or what other people are suggesting. Choose your ROM (or several, it's fairly easy to install them so try a few!), and download it. You should get a .zip that is approx. 150-170 MB in size. As an aside you will probably also want to download the corresponding GApps package HERE and put that on the SD card as well. I think some ROMs have that included, but if you boot into a room and it doesn't have the Play store installed, you need to go back into safestrap and install the GApps package over it. You don't have to delete and recreate the rom slot, just go back into install and install it over. When I say corresponding, the different packages go with different versions of Android so for example the one labelled 20110307 would go with Android 2.3.4 which is Gingerbread, the version that Steel Droid uses.
For whichever one you choose, the install process is mostly the same. Reboot your phone, and after the Motorola Logo comes up, you should see the Safestrap splash screen. To get into the recovery menu you have to hit the "Menu" soft-key (the one all the way on the left) within 10 seconds so keep an eye on it.
From the recovery menu go into "Boot Options" You should see 5 options, rom-slot 1-4 and Stock. When you want to switch what ROM you are booting you select on the corresponding slot, and hit activate, then you can reboot through the menu option and it will start that ROM.
To install you will go into "Boot Options" chose whichever rom slot you want (most likely #1). You will have to create that slot, which can take a few minutes. After the slot is created, back out of boot options, and go to "Install". Find the .zip of whichever ROM you chose, and select that to install, and then you can install the corresponding GApps package.
After the install is complete, you can reboot (make sure it says rom slot 1 is selected up to), and it should boot into the Setup process of the ROM. If you ever need to go back to stock, just reboot, go back into Safestrap > Boot options, activate the "Stock" one and boot into that.
A few notes, if you want to switch ROMs, or install multiple ROMs you can do that using the different rom slots with a few exceptions. The Cyanogen Mod 10 and the Avatar Rom (most Jelly bean ones I think) have to be installed in rom slot 1, so if you're doing those and another like Steel Droid, put the Jellybean one in rom slot 1 and the Gingerbread on in rom slot 2. Also if you want to install a different ROM, it's generally best to just completely erase the rom slot and recreate it, then install the different ROM in the newly created rom slot. You can always create backups with Safestrap and restore them with Safestrap. Oh and make sure your phone has a decent charge before doing a lot of the safestrap stuff (I would say at least 60%) you can also have the phone plugged in while doing this stuff, but I'm not always confident it is charging so try and get it charged up before hand.
Finally, if you ever mess up to the point where you're worried that you broke the phone, (boot loops or it is stuck on the Motorola Logo) you can download this restore tool HERE. This should completely wipe and restore the stock software on your phone. It will bring it back one version previous though, so be sure to go through the standard update process to bring it back to 5.7.906 so that the root tool will work. This tool has saved me a few times and is pretty easy to run.
Sorry, I know that is a lot of stuff and looks pretty scary. It really is just a few steps that you should research and make sure you are comfortable doing.
1: Get Root access on the stock software on the phone
2: Install safestrap and flash the custom recovery
3: Boot into recovery and install whichever custom ROM you want
If you have any questions feel free to ask!
Much appreciated !!! ..... i will try these steps as soon as i get my phone..... hope it doesnt make a difference if my D3 is an unlocked GSM phone because all service providers in my country uses GSM
Tha slayer said:
Much appreciated !!! ..... i will try these steps as soon as i get my phone..... hope it doesnt make a difference if my D3 is an unlocked GSM phone because all service providers in my country uses GSM
Click to expand...
Click to collapse
if you are using gms you may need Rom version with a modified build prop, most of the roms threads will have a modified version for GMS, in the OP or somewhere in the thread. if you can't find it just ask in the original rom thread
also some good how to videos here https://sites.google.com/site/tomsgt123/all-videos/videos-page-4
Good afternoon all,
I have an HTC One PN072. I've flashed the phone from Sprint to Cricket. They were very adamant about me not "resetting" the phone as it will remove the information, or flash they've added.
I've done several searches and can't seem to find a thread indicating 1) if this is possible and 2) a guide to doing so. The phone already is rooted and has TWRP on it as well.
If anyone knows of a thread I would love a link to a guide.
heartspains88 said:
Good afternoon all,
I have an HTC One PN072. I've flashed the phone from Sprint to Cricket. They were very adamant about me not "resetting" the phone as it will remove the information, or flash they've added.
I've done several searches and can't seem to find a thread indicating 1) if this is possible and 2) a guide to doing so. The phone already is rooted and has TWRP on it as well.
If anyone knows of a thread I would love a link to a guide.
Click to expand...
Click to collapse
I have a Sprint One fully flashed to Verizon and I flash custom ROMs all the time without any problems. I have never lost any settings and I don't even have to re-activate my phone. I would think that as long as you dont use Bootloader to flash a complete RUU image you should be fine. Goin s-off if your not already might cause issues here as well. (If someone knows for sure please correct me) I would say just download a ROM and install it with TWRP. I have updated firmware as well with no issues as well, however the firmware I upgraded with did not contain a radio update, which I am hesitant to do since I imagine that will effect my flash. I did my flash myself but it seems like a headache re-doing it.
electroblood said:
I have a Sprint One fully flashed to Verizon and I flash custom ROMs all the time without any problems. I have never lost any settings and I don't even have to re-activate my phone. I would think that as long as you dont use Bootloader to flash a complete RUU image you should be fine. Goin s-off if your not already might cause issues here as well. (If someone knows for sure please correct me) I would say just download a ROM and install it with TWRP. I have updated firmware as well with no issues as well, however the firmware I upgraded with did not contain a radio update, which I am hesitant to do since I imagine that will effect my flash. I did my flash myself but it seems like a headache re-doing it.
Click to expand...
Click to collapse
The wipes in TWRP usually recommended before flashing a custom rom don't remove their flashed data?
heartspains88 said:
The wipes in TWRP usually recommended before flashing a custom rom don't remove their flashed data?
Click to expand...
Click to collapse
Not that I have ever experienced. That was true on my EVO LTE and has so far been true on my One. I have the newest TWRP and in the past two days I have flashed EclipticOne, Elegencia and Insert Coin. On my old Droids Clockwork recoveries reset worked fine as well. DONT do a factory reset from inside the ROM. I have not tried it on my One, but on my EVO and my Droid 1/2/3 phones that would undo parts of a flash and I would have to reactivate. If I were you I would just work within my current firmware and flash what was available.
It is possible for you to flash your phone back to Cricket for free but its requires a lot of setup and can be a real pain in the ass. Getting 3G on Verizon was particularly painful and I have many screen shots and pages of notes on the actual procedure. When I upgraded from my EVO to the One I managed to get it right the first time by following my notes but it was still a serious hassle.
electroblood said:
Not that I have ever experienced. That was true on my EVO LTE and has so far been true on my One. I have the newest TWRP and in the past two days I have flashed EclipticOne, Elegencia and Insert Coin. On my old Droids Clockwork recoveries reset worked fine as well. DONT do a factory reset from inside the ROM. I have not tried it on my One, but on my EVO and my Droid 1/2/3 phones that would undo parts of a flash and I would have to reactivate. If I were you I would just work within my current firmware and flash what was available.
It is possible for you to flash your phone back to Cricket for free but its requires a lot of setup and can be a real pain in the ass. Getting 3G on Verizon was particularly painful and I have many screen shots and pages of notes on the actual procedure. When I upgraded from my EVO to the One I managed to get it right the first time by following my notes but it was still a serious hassle.
Click to expand...
Click to collapse
i was thinking about getting my one flashed to verizon but how does it work?? say i get my phone flashed.. is it verizon pre paid?? does that come with unlimited data?? text & talk?? how much would my bill be a month? sorry for all the questions
I apologize, so just to be as clear as possible, if you follow all of the wipes that roms usually ask you to perform in TWRP then you should be fine? However, do not perform a factory reset in the rom itself once loaded?
Doing a wipe through TWRP's wipe feature is fine as long as you dont go into 'Advanced' and mess with settings. Do not do the factory reset within the ROM once the ROM is loaded. If, while installing a ROM, the installer wants to do a wipe, that is fine as well.
Hi all,
I am I a position where I can get unlimited tethering, of which I am grateful for. I purchased the phone from Vodaphone and then moved to another provider. Because its a third party phone, tethering is not detected.
So, I accidentally updated the software version of the 510 to 1.51.161.12 and then to 1.51.161.14 and my tethering application took a MASSIVE hit.
Tethered to an Xbox one, I now get huge packet loss, very low MTU, huge latency and slow speeds, which was not present before the update. I have contacted the HTC devs to let them know about the issue. I have already troubleshooted all my devices, factory reset, wiped the cache etc...
I wish to roll back the version. I realise in order to do this I will need to root my phone and flash a ROM. The only Kernel I could find was on the htcdev website and was version 1.51.161.10 from vodaphone. Is this a stock ROM?
Can anyone assist me in safely flashing my phone, I have never done this before and I would like to keep my unlimited tethering and phone in working condition. I did Google it but I couldn't find any decent results.
What is a safe guide to follow? I am completely inexperienced at this and would really appreciate the help.
Is dip_spits guide appropriate for a a UK carrier, does it matter? I almost used this guide
https://support.digitalendpoint.com/hc/en-us/articles/204812787-How-to-root-the-HTC-Desire-510 -until I realised that I need philz recovery for 64bit. Will using the dip_spit guide lock my carrier again?
What ROM can I use after rooting. Why is it so hard to find information on HTC 510 rooting and ROMs
I am looking for a safe way of doing this and have posted multiple times on XDA, but nobody can help me. The reason I am doing this is to restore functionality to my tethering, which has broken for no apparent reason.
Thanks
Benjive said:
Hi all,
I am I a position where I can get unlimited tethering, of which I am grateful for. I purchased the phone from Vodaphone and then moved to another provider. Because its a third party phone, tethering is not detected.
So, I accidentally updated the software version of the 510 to 1.51.161.12 and then to 1.51.161.14 and my tethering application took a MASSIVE hit.
Tethered to an Xbox one, I now get huge packet loss, very low MTU, huge latency and slow speeds, which was not present before the update. I have contacted the HTC devs to let them know about the issue. I have already troubleshooted all my devices, factory reset, wiped the cache etc...
I wish to roll back the version. I realise in order to do this I will need to root my phone and flash a ROM. The only Kernel I could find was on the htcdev website and was version 1.51.161.10 from vodaphone. Is this a stock ROM?
Can anyone assist me in safely flashing my phone, I have never done this before and I would like to keep my unlimited tethering and phone in working condition. I did Google it but I couldn't find any decent results.
What is a safe guide to follow? I am completely inexperienced at this and would really appreciate the help.
Is dip_spits guide appropriate for a a UK carrier, does it matter? I almost used this guide
https://support.digitalendpoint.com/hc/en-us/articles/204812787-How-to-root-the-HTC-Desire-510 -until I realised that I need philz recovery for 64bit. Will using the dip_spit guide lock my carrier again?
What ROM can I use after rooting. Why is it so hard to find information on HTC 510 rooting and ROMs
I am looking for a safe way of doing this and have posted multiple times on XDA, but nobody can help me. The reason I am doing this is to restore functionality to my tethering, which has broken for no apparent reason.
Thanks
Click to expand...
Click to collapse
Okey.....a lot of questions.
Firstly, if you are 64 bit there is no need to use philiz touch recovery. There is TWRP recovery for our device. You can get it here:http://twrp.me Don't search HTCDev for 64bit ROM's. The only thing there are kernel source files. The carrier lock is not in any way connected with the operating system (at least thats what I think). And it's highly doubtful that the lock will reapear. The reason that you can't find a lot of guieds about our device it's mainly because the majority of devs here on XDA are from the USA. In the USA they sell the 32 bit version of the phone and the software is very different from the 64 bit.
Now lets talk about ROM's.
If you want pure stock rom you can search for it here mega:///#F!3Zo10Zya!-NbM_2RWWecFlc5mH9bLbA
If you want a custom rom you can get this one http://forum.xda-developers.com/desire-510/htc-desire-510-64-bit-eu--international-version/cyanogenmod-12-1-msm8916-64bit-t3281744
And if you'd like a debloated version of the stock you can get this one: http://forum.xda-developers.com/desire-510/htc-desire-510-64-bit-eu--international-version/android-4-4-3-stock-os-debloated-64bit-t3361689
denny.hell said:
Okey.....a lot of questions.
Firstly, if you are 64 bit there is no need to use philiz touch recovery. There is TWRP recovery for our device. You can get it here:http://twrp.me Don't search HTCDev for 64bit ROM's. The only thing there are kernel source files. The carrier lock is not in any way connected with the operating system (at least thats what I think). And it's highly doubtful that the lock will reapear. The reason that you can't find a lot of guieds about our device it's mainly because the majority of devs here on XDA are from the USA. In the USA they sell the 32 bit version of the phone and the software is very different from the 64 bit.
Now lets talk about ROM's.
If you want pure stock rom you can search for it here mega:///#F!3Zo10Zya!-NbM_2RWWecFlc5mH9bLbA
If you want a custom rom you can get this one http://forum.xda-developers.com/desire-510/htc-desire-510-64-bit-eu--international-version/cyanogenmod-12-1-msm8916-64bit-t3281744
And if you'd like a debloated version of the stock you can get this one: http://forum.xda-developers.com/desire-510/htc-desire-510-64-bit-eu--international-version/android-4-4-3-stock-os-debloated-64bit-t3361689
Click to expand...
Click to collapse
Ok so here is what happened when I rooted.
I unlocked the boot loader and made a recovery using philz touch. The PROBLEM is that I didn't have an SD card installed so what happened is philz touch partioned part of my phones memory. So I go to root and it is successful.
Now I got to recovery to install back the system because I was not happy with the way some of the apps were running and I want to install the stock vodpahone RUU on zubaggys page. I go ahead and recover but now it has taken more memory. I am now running my old ROM and kernel with less than 1 gig of free memory!!
All I want to do now is reinstall the stock vodaphone
Another question. When I was rooted, I downloaded barnacle tether and messed with the transmit power in the settings. I disabled and uninstalled. I also downloaded port forwarder ultimate and messed with the setting but uninstalled.
Will this affect my ROM installation, will it be fresh.
Thanks.
Benjive said:
Ok so here is what happened when I rooted.
I unlocked the boot loader and made a recovery using philz touch. The PROBLEM is that I didn't have an SD card installed so what happened is philz touch partioned part of my phones memory. So I go to root and it is successful.
Now I got to recovery to install back the system because I was not happy with the way some of the apps were running and I want to install the stock vodpahone RUU on zubaggys page. I go ahead and recover but now it has taken more memory. I am now running my old ROM and kernel with less than 1 gig of free memory!!
All I want to do now is reinstall the stock vodaphone
Another question. When I was rooted, I downloaded barnacle tether and messed with the transmit power in the settings. I disabled and uninstalled. I also downloaded port forwarder ultimate and messed with the setting but uninstalled.
Will this affect my ROM installation, will it be fresh.
Thanks.
Click to expand...
Click to collapse
If philiz touch partitioned the phone then it's a miracle that it's still working. At this point I will suggest you flash TWRP because it has a more clean interface and there is no way you'd mess up something. Afterwards use it to format every single partition you can find with it. Beware that with this you will delete all data including the OS. I am not 100% percent that this will work because I haven't seen a situation like yours.
denny.hell said:
If philiz touch partitioned the phone then it's a miracle that it's still working. At this point I will suggest you flash TWRP because it has a more clean interface and there is no way you'd mess up something. Afterwards use it to format every single partition you can find with it. Beware that with this you will delete all data including the OS. I am not 100% percent that this will work because I haven't seen a situation like yours.
Click to expand...
Click to collapse
Jeez, I guess i have got myself in a bit of a sticky situation. I followed dips rooting procedure and it explicitly stated not to use twrp and use Philz touch instead for 64 bit phones. It also didn't state to use an Sd card.
We are talking in two threads here, so I suggest, to help other users with a stock revert, that we continue in Zubaggys thread. You are being a great help and I really appreciate you giving me your time.
I have been searching for custom ROMs for a couple days, yet haven't come across any that are compatible with the G973W. I have noticed a few that don't specify, and just say "S10", but I would like confirmation.
I would also like to know if it is possible to create an image/ROM of my devices current state as a sort of restore point. I know it's kind of a nooby question, but I am having a hard time finding that information. Thanks!
Your phone has the same snapdragon processor as the G973U. I can't give a direct yes or no answer, but I have seen root options for that phone.
Now your task is to see if what works for G973U will work for G973W (I bet it would since it's basically the same phone).
If you can't find a definite answer, make backups and download Odin and copy of your firmware just in case you brick the phone and give it a try.
malcolmy said:
Your phone has the same snapdragon processor as the G973U. I can't give a direct yes or no answer, but I have seen root options for that phone.
Now your task is to see if what works for G973U will work for G973W (I bet it would since it's basically the same phone).
If you can't find a definite answer, make backups and download Odin and copy of your firmware just in case you brick the phone and give it a try.
Click to expand...
Click to collapse
Thanks for the reply! I was thinking the same thing. Perhaps only carrier specific software might break. I would just go ahead and try it, but I'm having a really tough time finding how to make a copy of my phone the way it currently is. It is currently rooted, with TWRP and Magisk. I also have Odin, and Android Studio with ADB. Just not sure how to pull the current firmware.
TacoDeMuerte said:
Thanks for the reply! I was thinking the same thing. Perhaps only carrier specific software might break. I would just go ahead and try it, but I'm having a really tough time finding how to make a copy of my phone the way it currently is. It is currently rooted, with TWRP and Magisk. I also have Odin, and Android Studio with ADB. Just not sure how to pull the current firmware.
Click to expand...
Click to collapse
Good you're rooted, when I wrote my reply all I had in mind was root.
However, backup is easier with TWRP. Just go into recovery and then to backup. Backup everything.
There's a bug I have read about with one version of TWRP that wouldn't backup to SD card. So if you face any issues there just backup to phone storage.
Since you're rooted, and can make a nand backup with TWRP, try the available ROMS for G973U. If anything goes south, restore in TWRP. Just make sure of the compatible versions of Android/BL/modem/TWRP between your current phone as it is, and the ROM you'll be using. Because your purpose now should be (I believe) is to test compatibility between S10 U and W versions. If all goes well, go nutz.
So I made a back-up and flashed a ROM for the U variant, but ended up in a boot loop. Wiping and restoring via TWRP also resulted in a boot loop. The only way out was to download stock firmware and flash via Odin. I had followed all of the relevant instructions to the letter, so if any one else wants to try a ROM made for U devices on a W variant, do so at your own risk and make sure you have the correct stock firmware and Odin ready. I might try again down the road just in case something went wrong on my part.