[Galaxy S III Original Android Development] curiousrom:
Network Problems, Internal Storage, Bootloop, Best Kernel & Off Topic

"...The internal storage was not accessible" - From the phone itself in System, when connected to a computer via MTP or ADB, in TWRP > File Manager or with TWRP connected to a computer as MTP & ADB is enabled by default in TWRP?

Anyway that calls for a thorough Format Data in TWRP Recovery instead of a simple Wipe before installing LineageOS to avoid future problems IMO. See my reply to [MENTION=7148817]GalaxyMaster_P[/MENTION] in the bottom of this recent post: Hacked LineageOS Reboots, Bootloops, Xposed & Corrupted Data

"...I'm having network issue." - Try long press Power button > long press either Power off or Restart > Reboot to safe mode. If the problem is solved then it's an app you installed.

Check Settings > Wireless & networks > More > Cellular networks > Access Point Names > and make sure it is the ones your provider recommends.

Is it the same intermittent network connection if you enable Cellular Data or in > Settings > Wireless & networks > More > Cellular networks > Preferred network type > 2G?

Did you check with your cellular provider if there is a problem in your region with their network?

Check S3 How to do a very important EFS Partition Backup - No Service Fix (by restoring the EFS partition from a backup) and Samsung stock firmware & LineageOS Super Clean Install > step #13 if you don't have a EFS Partition or a full Nandroid backup.

You could try to troubleshoot using the free MatLog: Material Logcat Reader > Settings > Clear > File > Record > observe Network connecting/disconnecting for a minute or two without doing anything else on the phone > then Stop MatLog > Send > Send Log as attachment (File > Save as works too) and open it in Wordpad on a computer for example to study it or post here after renaming it with a .txt extension.

You could also try this:

"...I've done screen recording..." - That must be one the most boring video I ever saw & that sharing site is full of cr@ppy popup windows. :) (Try imgur next time and a direct link to the screen recording. For example this (also boring) one about LOS in-call minimum volume was made with the stock Lineage Recorder like you did: https://i.imgur.com/piuyvJs.mp4

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Try the suggestions above & also what [MENTION=7746932]Robert-R[/MENTION] said. Check also here for SIM hardware troubleshooting tips: https://thedroidguy.com/2018/04/how-to-solve-samsung-galaxy-s3-no-sim-card-problem-57290

Try testing SIM for more than 5 hours when running Samsung stock firmware.

There could be dozens of different reasons for a bootloop so you can't say that you have the same problem as qb74 which was using a custom beta kernel. Try booting without a SIM card as you reported Network problems when using other kernels & firmwares in other threads.

You did not say if you got into a bootloop after a system crash or by rebooting manually: soft reboot, hard reboot, power off then turning on again, etc.

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Best Kernel for Battery Life?

Nobody knows because nobody ran tests & benchmarks comparing different kernels for i9300 running Lineage 14.1 @ the present as far as I know.

From the Boeffla-Kernel FAQ: "...99% of the time battery drain issues come from apps, the rom or background processes.'

Interesting article by the kernel developer of ElementalX The truth about kernels and battery life

Anyway there are a number of free kernel manager apps including Kernel Adiutor that you can use to tweak (CPU frequency, Governor, I/O Scheduler, etc) of the stock LineageOS 14.1 for i9300 kernel but make 100% sure that you have a full recent TWRP backup & full backup of your internal storage & > Settings > Backup & reset setup properly & backups of your messenger apps like WhatsApp for example as it is easy to mess-up your system as described in the FAQ's linked above.

Several of the settings suggestions in my post here can have a much bigger impact on battery life than any custom kernel & tweaking including something as basic as using the minimum screen brightness level that you are comfortable with: S3 LineageOS Battery Drain Troubleshooting & Optimization

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You are in the wrong thread as this one is for LineageOS 14.1 for i9300.

Go here instead: HYPER-ROM for Galaxy S3

If you don't see it here then no: https://download.lineageos.org/i9300 Check this post for news: Bunch of Links: S3 i9300 LineageOS, Developer & Oreo Project

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